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Temporal analysis of pasture vegetation cover in central-western Brazil using remote sensing
No full textReceived: January 19th, 2024 ; Accepted: April 7th, 2025 ; Published: April 20th, 2025 ; Correspondence: [email protected], [email protected] is the world's leading exporter of beef, consolidating beef cattle farming as an important branch of national livestock farming. The expansion of livestock farming and agriculture in recent decades has resulted in a notable increase in pasture areas in Brazil. However, the country faces the growing challenge of pasture degradation, a problem that threatens sustainability and food production. On the other hand, livestock farming in Brazil's Central-West region, the country's largest cattle-producing area, particularly in the state of Goiás, can cause environmental damage when sustainable practices are disregarded. Thus, the objective of this article was to evaluate pasture degradation, at different levels, in the Ribeirão Serra Negra Watershed, in the municipality of Piracanjuba, Goiás, Brazil. Using images from the Sentinel-2A orbital sensor, the NDVI (Normalized Difference Vegetation Index) vegetation index and the vegetation cover classes of pastures were obtained between 2017 and 2021. During this period, the results showed that more than 98% of the areas had some level of degradation, with an average coverage of 6,586.1 ha. There was an upward evolution in the levels of vegetation cover between 2017 and 2019, with the best pasture conditions predominating in 2019. These assessments help identify areas that require greater attention and often necessitate conservation practices and management plans. In this context, monitoring degraded areas is a practice that facilitates the improvement of existing pastures, promotes the rational management of inputs, conserves natural resources, and aligns with development programs focused on sustainability
Introductory learning material to support workplace adaptation
No full textMagistritöö
Ergonoomika õppekavalVaatamata erinevate riikide poliitikale, mis toetab puuetega inimeste tööturul osalemist,
jääb nende tööhõive tase oluliselt madalamaks võrreldes üldrahvastiku omaga.
Kirjanduses on viidatud mõjutatajateks tööandjate hoiakud, teadmatus ning
organisatsiooniline valmidus. Magistritöö eesmärgiks on koostada õppematerjal, mis
toetab ergonoomika põhimõtete rakendamist töötamiskohtade kujundamisel. Magistritöö
on osa Erasmus+ projektist ErgoArt, mille eesmärk on täiustada olemasolevaid
kõrghariduse õppekavasid ning pakkuda süsteemset lähenemist õpetamisele ja teadmiste
jagamisele teistele kohalikele haridusasutustele. Magistritöös kasutati kvalitatiivset
metoodikat: viidi läbi intervjuud 10 tööandja ja 10 puudega töötajaga, küsitlusele
internetis vastas 43 inimest. Tulemused näitasid, et tööandjad on valmis tegema töökoha
kohandusi mõõdukalt, tingimusel, et kulud on mõistlikud. Samas tõid töötajad esile
ligipääsetavuse probleeme ja ebapiisavat sotsiaalset toetust kollektiivis. Ergonoomika
tudengite seas läbiviidud küsitlus tõi esile, et enamik peab puuetega inimeste kaasamist
tööturule väga oluliseks, kuid seniseid teadmisi töökohtade kohandamisest ja vastavatest
meetoditest ei seostata töökohtade kujundamisega puuetega inimestele. Selle kitsaskoha
lahendamiseks koostati õppematerjal, mis konspektina aitab ühtlustada tudengite keskseid
ergonoomikateadmisi ning rõhutab sihtgrupi tundmise vajadust universaalse disaini
protsessis. Õppematerjal töökohtade kujundamiseks sai tudengitelt positiivse hinnangu.
Tulevikus võiks materjali rakendada laiemalt ka majandusõppe valdkonnas, et tõsta
juhtide teadlikkust, mis võimaldaks neil paremini toetada töökohtade kohandamist
puuetega inimestele.Despite national policies supporting labour market participation for people with
disabilities, their employment rates remain significantly lower compared to the general
population. Employer attitudes, insufficient awareness, and organisational preparedness
are frequently identified as influencing factors in the literature. The aim of this thesis was
to develop educational materials supporting the application of ergonomic principles in
workplace design. The thesis is part of the Erasmus+ project ErgoArt, which seeks to
enhance existing higher education curricula and promote a systematic approach to
teaching and knowledge dissemination among local educational institutions. A qualitative
methodology was employed, including interviews with 10 employers and 10 employees
with disabilities, alongside responses from 43 participants to an online survey. Results
indicated employers' willingness to implement moderate workplace adaptations,
contingent on reasonable costs. Conversely, employees underscored issues relating to
accessibility and inadequate social support within workplaces. Additionally, a survey of
ergonomics students revealed a general recognition of the importance of integrating
people with disabilities into the labour market, yet identified gaps in students' existing
knowledge regarding methods and strategies for inclusive workplace design. To bridge
these gaps, educational material was developed, designed conceptually to unify students'
foundational ergonomics knowledge and emphasise awareness of diverse target groups
within the universal design process. This material was positively assessed by students.
Looking forward, there is potential for broader application of these educational materials
within business curricula, aimed at increasing managerial awareness and competence in
effectively adapting workplaces for people with disabilities
The effect of different ash treatments on the growth of norway spruce
No full textMagistritöö
Metsamajanduse ja metsaökoloogia õppekavalEestit katavad sood umbes 22,3% maismaa pindalast, nende kuivendamine ning turbatootmisest mahajäetatud freesväljakud mõjutavad oluliselt keskkonda. Puitbiomassi kasutatavates koostootmisjaamades jäätmena tekkiv toitainerikas puutuhk sobib oma omadustelt taimekasvu parandavaks väetiseks. Magistritöö eesmärk oli uurida puutuhaga väetamise mõju hariliku kuuse kasvule ammendatud freesturbaväljadel Ulilas ja Pindis. Katsealadel analüüsiti kuuse kasvunäitajaid ning turba keemilist koostist erinevate tuhakoguste lisamisel. Tulemused näitasid, et puutuhaga väetamine parandas oluliselt kuuskede kõrguskasvu ja juurekaela diameetrit, eriti puutuha10 t/ha koguse korral, muutes turba pH-d ja toitainesisaldust taimede kasvuks soodsamaks. Suurem tuhahulk kogusega 15 t/ha ei andnud täiendavat kasvuefekti. Turba pH ja toitainete sisaldus turbas mõjutasid puude kasvu märkimisväärselt. Kontrollaladel esines kuuskedel toitainevaegus ning taimede suremus oli kõrge. Kuuskede kasvule avaldasid mõju ka ilmastikutingimused: statistiline analüüs kinnitas töötluste vahel olulisi erinevusi alates viiendast kasvuaastast. Töös saadud tulemused on aluseks puutuha kasutamisel jääksoode metsastamisel.About 22.3% of Estonia’s land area is covered by peatlands, their drainage and peat production impact significantly the environment, while wood ash from biomass heating power plants remains production of a large amount of nutrient-rich wood ash. The aim of this master’s thesis was to investigate the effect of wood ash fertilization on the growth of Norway spruce (Picea abies) on exhausted milled peat extraction sites in Ulila and Pindi. Growth indicators of spruce and the chemical composition of peat were analyzed under different ash application rates. The results showed that wood ash fertilization significantly improved spruce height growth and root collar diameter, especially at a moderate dose of 10 t/ha, by increasing peat pH and nutrient availability. Higher ash dose 15 t/ha did not provide additional growth benefits. Peat pH and nutrient content had a significant effect on growth. On control plots, nutrient deficiencies and high mortality of trees were observed. Weather conditions also influenced spruce growth: statistical analysis confirmed significant differences between treatments starting from the fifth growing season. The study provides a basis for optimizing the use of wood ash in afforestation of abandoned peatlands
The use of threaded inserts in 3D printed components
No full textBakalaureusetöö
Tehnika ja tehnoloogia õppekaval3D-printimist kasutatakse laialdaselt prototüüpide ja ka toodete valmistamisel, kuid keermesliidete vastupidavus 3D prinditud detailides on sageli piiravaks teguriks.
Töö eesmärk on uurida, kas keermestatud sisetükid annavad tugevama keermesliite FFF (FDM) tehnoloogial 3D prinditud detailides võrreldes lõigatud keermetega.Tõmbekatsed viidi läbi nelja erineva 3D prinditava materjaliga, milleks olid PLA, ABS, PC, PAHT-CF, kasutades nii sisetükke kui ka prinditud keermeid. Kasutati keermeid M3 keermesammuga 0,5 mm, M4 keermesammuga 0,7 mm, M5 keermesammuga 0,8 mm, M6 keermesammuga 1 mm ja M8 keermesammuga 1,25 mm. Maksimaalse vastupanu välja selgitamiseks tõmbejõule viidi läbi tõmbekatsed.
Sisetükkide kasutus parandas oluliselt keermesliite tugevust PLA puhul M3, M4, M5 ja M8 keermesuurustel, ABS-i puhul kõikidel keermesuurustel, PC puhul M3 ja M6 keermesuurustel ja PAHT-CF puhul M3 keermesuurusel. Nende 3D prinditavate materjalide ja keermesuuruste puhul sisetükid sobivad hästi tehnilisteks rakendusteks, kui on vaja tugevamat keeret mida on vaja korduvalt kokku panna ja lahti võtta.3D printing is widely used for prototyping as well as manufacturing products, but the durability of threads in 3D printed parts is often a limiting factor.
The aim is to investigate whether threaded inserts provide a stronger threaded joint in FFF (FDM) 3D-printed parts compared to cut threads. Tensile tests were conducted using four different 3D-printable materials: PLA, ABS, PC, and PAHT-CF. Both inserts and printed threads were tested. Thread sizes used included M3 with a 0,5 mm pitch, M4 with a 0,7 mm pitch, M5 with a 0,8 mm pitch, M6 with a 1 mm pitch, and M8 with a 1,25 mm pitch. Pull out tests were carried out to determine the maximum resistance to pulling force.
The use of inserts significantly improved the strength of threaded joints for PLA with M3, M4, M5, and M8 thread sizes, for ABS with all thread sizes, for PC with M3 and M6 thread sizes, and for PAHT-CF with the M3 thread size. For these 3D-printable materials and thread sizes, inserts are well-suited for technical applications where a stronger thread is required that needs to be assembled and disassembled repeatedly
Remotely piloted aircraft for monitoring greenhouse gases in dairy production systems
No full textReceived: January 31st, 2024 ; Accepted: April 16th, 2025 ; Published: May 15th, 2025 ; Correspondence: [email protected] monitoring of greenhouse gas (GHG) emissions in dairy cattle facilities is essential for understanding and mitigating the environmental impact of livestock farming. Among the main gases emitted in dairy production systems, methane (CH4) and carbon dioxide (CO2) play significant roles in global warming. The objective of this research was to evaluate the spatial variability of CH4 (ppm) and CO2 (ppm) concentrations, as well as environmental variables (dry bulb temperature, tdb, °C, and relative humidity, RH, %), in a compost barn dairy production system. For gas concentration monitoring, an electrochemical sensor was used for CH4 and a non–dispersive infrared (NDIR) sensor for CO2. For the environmental variables, a Hobo® MX2301A datalogger was used, and both pieces of equipment were attached to a remotely piloted aircraft (RPA), the DJI Matrice 350. Measurements were carried out over three days, with flights conducted over the facility's roof. The data obtained were analysed using geostatistics to characterise spatial variability of the GHG. A strong spatial dependence was observed in gas concentrations and environmental variables. The highest concentrations of CH4 (129–134.4 ppm) and CO2 (434–479 ppm) were recorded on the first day. Tdb ranged between 24.2 °C and 32 °C, while RH fluctuated between 38.8% and 68%. The use of RPA proved to be an efficient tool for GHG monitoring, allowing the identification of spatial distribution patterns. This technology provides a novel approach to measuring GHG emissions, addressing the environmental challenges of the agricultural sector
Perception of workload of AS Eesti Post postal couriers and its influencing factors
No full textMagistritöö
Majandusarvestuse ja finantsjuhtimise õppekavaLõputöö eesmärk oli analüüsida AS Eesti Posti postikullerite tajutud töökoormust ning selle seoseid töömotivatsiooni ja töörahuloluga. Töö teoreetiliseks aluseks oli töönõudmiste ja -ressursside (JD-R) mudel, mille kaudu vaadeldi tööalaste nõudmiste (füüsiline ja vaimne töökoormus) ning tööressursside (autonoomia, tehniline tugi, töötasu) mõju tööheaolule.
Empiirilise uurimuse läbiviimiseks koostati struktureeritud küsimustik, mis jagunes seitsmeks plokiks ja baseerus rahvusvahelistel tööheaolu hindamise mudelitel (COPSOQ, NASA-TLX). Küsimustikule vastas 53 postikullerit eri piirkondadest. Andmeid analüüsiti kvantitatiivselt, kasutades sagedusi ja jooniseid.
Tulemused näitasid, et töökoormus on postikullerite seas üldiselt kõrge, eriti tippperioodidel ning ilmastikuolude halvenemisel. Füüsiline väsimus, tehnoloogiline stress ja tööõiguse tajumine mõjutasid tugevalt töötajate rahulolu ja motivatsiooni. Töötasu mittevastavus koormusele ning ebaühtlane tööjaotus langetasid tööga rahulolu. Samas toetasid autonoomia ja töö tähenduslikkus sisemist motivatsiooni.
Töö tulemusel esitati soovitused töökorralduse parandamiseks, töökoormuse seireks ning töötajate heaolu toetamiseks. Uuring kinnitas mitmeid püstitatud hüpoteese ning tõestas JD-R mudeli sobivust logistikasektori tööanalüüsis.The aim of the thesis was to analyze the perceived workload of postal couriers at AS Eesti Posti and its relationship with work motivation and job satisfaction. The theoretical basis of the work was the job demands and resources (JD-R) model, through which the impact of job demands (physical and mental workload) and job resources (autonomy, technical support, salary) on job well-being was examined.
To conduct the empirical study, a structured questionnaire was developed, divided into seven blocks and based on international occupational well-being assessment models (COPSOQ, NASA-TLX). 53 postal couriers from different regions responded to the questionnaire. The data were analyzed quantitatively using frequencies and figures.
The results showed that the workload is generally high among postal couriers, especially during peak periods and when weather conditions deteriorate. Physical fatigue, technological stress and perception of labor rights strongly influenced employee satisfaction and motivation. The mismatch between the salary and the workload and the uneven distribution of work lowered job satisfaction. At the same time, autonomy and meaningfulness of work supported intrinsic motivation.
The work resulted in recommendations for improving work organization, monitoring workload, and supporting employee well-being. The study confirmed several hypotheses and proved the suitability of the JD-R model for work analysis in the logistics sector
INTERREG project: Cooperation for Rural Governance* Rural Proofing. Cooperation for better sparsely populated rural, coastal and mountain focused governance (Coop4RURALGov)
No full textThe overall aim of the comparative study was to compare the current state of rural proofing as well as ways to better integrate the consideration of rural needs into policy planning and implementation in the Bulgaria, Estonia, Ireland, Navarre region (Spain) that are partners in Coop4RuralGov project. The survey used a mixed methods approach combining document review, a questionnaire survey of rural policy stakeholders and focus groups for data collection.
The four countries in the study (Bulgaria, Estonia, Ireland, and Spain) are at different stages in the development and implementation of their rural proofing mechanisms. Ireland and Estonia have developed specific rural proofing guidelines for national-level policies, and rural proofing should be conducted if the initial screening of a draft policy or strategy indicates that it may have a differential impact on rural areas. However, the application of rural proofing has been inconsistent, and there has been no regular data collection to monitor its implementation. Spain legislated the requirement for rural proofing with a law passed in 2022, and the Foral Community of Navarre is in the process of developing its own legislation. Bulgaria has not established a dedicated rural proofing framework or legislation, and regional impacts are assessed within the broader framework of Regulatory Impact Assessment (RIA).
The questionnaire survey was an expert survey targeting rural policy stakeholders, who are involved in the development and implementation of rural and regional policies, programs, and initiatives, as well as in assessing their impacts and/or participating in stakeholder consultations at the national, regional, or local level. 208 responses were collected from the four countries on the stakeholders’ the experiences, perceptions, and challenges related to rural proofing.
The respondents represented a diverse mix of stakeholder types and policy levels, with varying experience in policy development, implementation, and consultation processes. Their involvement was strongest in the early stages of policy drafting, while fewer had experience with monitoring, ex-post impact assessment, or specifically assessing rural or regional impacts. Respondents in all four countries agreed that the current policy-making and planning processes have not adequately addressed rural needs, and over half reported that they often or always encounter policies and programs that fail to consider rural circumstances and needs. The common examples of this were the policies and programs related to infrastructure and service provision (particularly public transport, road networks, digital and emergency services, healthcare, and social welfare); the energy and environmental policies and measures, urban-centric planning and housing policies (notably in Spain and Ireland), and governance and funding mechanisms. Stakeholders demonstrated strong support for measures such as raising awareness among policy-makers; deeper rural stakeholder engagement, and integration of rural impact assessments into policy design.
The survey revealed widespread recognition of the importance of rural proofing, but it also highlighted major gaps in awareness of whether and how it is implemented, even in countries like Estonia and Ireland that have rural proofing guidelines in place. Two-thirds of respondents were familiar with the term “rural proofing,” but most were unsure or indicated that it is not actually implemented in their countries. In respondents’ experience, rural proofing, when conducted, was mostly applied in early policy stages using stakeholder engagement events and checklists, and the impact assessment focused on impacts on rural populations, jobs, and businesses, specific social groups and transportation. However, few could name concrete examples where rural impact assessment had meaningfully influenced policy change. There was strong support for making rural 6
proofing mandatory, particularly at the national level, but key barriers included limited public sector interest, lack of follow-up, and insufficient skills and knowledge.
Opinions on stakeholder engagement in the policy process indicated that current practices are often inadequate. Engagement tends to be concentrated in the early stages of policy processes, but this also varies between countries. Many respondents noted that consultations often occur too late, are hindered by a lack of skills, and fail to influence final decisions.
Effective rural proofing requires access to robust, detailed, and regularly updated data and analytical capacity to provide good input to policy-makers, yet existing practices do not fully meet these needs. Key challenges include lack of collection of sufficiently granular level for meaningful comparisons, lack of regular collection, timeliness of the data, fragmented data sources.
The discussions in the four focus groups focused on how to proceed. The Bulgarian stakeholders emphasized the need for mandatory rural proofing legislation, development of guidelines and support tools, capacity building, and institutional support, noting that current assessments are too broad and lack local specificity. In Estonia, the focus was on increasing awareness, clarification of “rural”, improving data quality, development of clear metrics, building local capacity for meaningful impact assessments beyond checklists and demonstration of successful models. Irish stakeholders prioritized decentralized, community-based decision-making with mandatory rural proofing supported by dedicated budgets, better interdepartmental coordination. Spanish stakeholders emphasized the need to foster bottom-up and local rural governance, incl. through technical and administrative support, development of toolbox, enhancing rural representation in decision-making bodies, simplifying administrative procedures, adjusting funding formulas, establishing specialized state agency to improve policy evaluation and coordination.
Some examples of innovative good practices demonstrated in the project included the use of existing data, such as the municipal web portal minuomavalitsus.ee in Estonia; AI-based tools in Ireland; stakeholder engagement initiatives, such as the Public Participation Network in Ireland and the G30 project’s expert groups; and virtual tools, such as an online module in New Zealand.
The main policy recommendations from the survey included:
• Make rural proofing mandatory and systematic, starting a national level with clear legislation and guidelines supported by enforcement and voluntary regional/local application.
• Establish a monitoring system with assigned responsibilities, and create a practical, accessible toolbox with guidance, digital tools, and good practice examples and detailed demonstration of cases on how it has been applied in practice.
• Clarify the scope and principles of rural proofing distinct from rural policy outcomes.
• Strengthen data and analytical capacity by leveraging already existing public databases, improving their interoperability, and developing advanced analytical (incl. AI) and visualization tools.
• Ensure meaningful stakeholder engagement through established procedures, transparent communication, and effective feedback mechanisms, supported by sustained resources and stakeholder network management.
• Raise policymakers’ awareness and capacity via top-down political commitment, bottom-up community support, training, outreach, and networking to build buy-in for rural proofing.INTERREG Europe. Co-funded by the European Union
Assessment of biocidal sensitivity of sanitary indicator microbes in bakery biofilm
No full textMagistritöö
Toiduainete tehnoloogia õppekavalBiokirmete moodustumine toidutööstuse seadmetel ja pindadel kujutab endast tõsist hügieeniprobleemi, mis suurendab mikrobioloogilise saastumise ja toidu riknemise riski. Enamik senistest teadusuuringutest on keskendunud biokirmete struktuurile ning nende tekkemehhanismidele, samas kui mikroobikoosluste tundlikkust biotsiidide suhtes on vähem uuritud. Selle uurimissuuna põhjalikum käsitlemine on oluline tõhusate ja sihipäraste desinfitseerimisstrateegiate väljatöötamiseks, mis aitaksid ennetada biokile moodustumist ning vähendada saastumisriski toiduainetööstuses.
Magistritöö eesmärk oli määrata pagaritööstuse biokirme mikroobne kooslus ja hinnata sellest isoleeritud mikroobide tundlikkust kolme erineva biotsiidi suhtes. Uuritav materjal koosnes ühe Eesti pagaritööstuse hügieeni-, toote- ja tooraineproovidest, millest isoleeritud mikroobid identifitseeriti MALD-TOF MS abil. Valitud isolaatidest (n=42) kasvatati mikrotiiterplaadis biokirmed. Biokirme kvantitatiivseks määramiseks kasutati kristallvioletti ja metaboolse aktiivsuse hindamiseks 2,3,5-trifenüültetrasooliumkloriidi. Biokirme biomassi ning metaboolse aktiivsuse vähenemist määrati spektrofotomeetriliselt.
Töö tulemustest selgus, et pagaritööstuse biokirmes esinesid nii grampositiivsed kui ka gramnegatiivsed bakterid, sh domineerisid sugukondade Bacillaceae, Staphylococcaceae, Moraxellaceae ja Micrococcaceae liigid. Mikroobide biotsiiditundlikkus varieerus liikide ja tüvede lõikes. Kolmest uuritud biotsiidist põhjustas etanool biokirme massi vähenemist oluliselt nõrgemalt kui alus-hape ja P3Oxysan ZS, mille toime biokirme massi vähenemisele oli omavahel sarnane. Biokirmete metaboolset aktiivsust pärssis kõige tõhusamalt alus-happe kombinatsioon, olles oluliselt efektiivsem kui P3Oxysan ZS ja etanool, mille mõju metaboolsele aktiivsusele oli sarnane. Kokkuvõtteks, tulemused rõhutavad vajadusele kohandada sanitatsioonistrateegiaid ja arendada biotsiiditundlikkuse hindamiseks standardiseeritud meetodeid, mis võtaksid arvesse biokirmete spetsiifilisi omadusi ja käitumist.Biofilm formation on equipment and surfaces within the food industry presents a significant hygienic challenge, increasing the risk of microbial contamination and food spoilage. While previous research has primarily focused on the structural characteristics and formation mechanisms of biofilms, the susceptibility of microbial communities within biofilms to biocides remains underexplored. A deeper understanding of this aspect is essential for developing effective and targeted disinfection strategies to prevent biofilm formation and reduce contamination risks in food processing environments.
The objective of this master’s thesis was to characterize the microbial composition of biofilms in the bakery industry and to assess the sensitivity of isolated microorganisms to three different biocides. The study material consisted of hygiene, product, and raw material samples from an Estonian bakery. Microbial isolates were identified using MALDI-TOF mass spectrometry. Biofilms were cultivated in microtiter plates from selected isolates (n=42). Crystal violet staining was used to quantify biofilm biomass, while metabolic activity was assessed with 2,3,5-triphenyltetrazolium chloride assay. Reductions in biofilm biomass and metabolic activity were measured spectrophotometrically.
The results demonstrated that bakery biofilms comprised both Gram-positive and Gram-negative bacteria, with dominant families including Bacillaceae, Staphylococcaceae, Moraxellaceae, and Micrococcaceae. Biocide sensitivity varied between species and strains. Among the tested biocides, ethanol caused a significantly weaker reduction in biofilm biomass compared to the acid-base combination and P3Oxysan ZS, which showed similar effects. The acid-base combination most effectively suppressed biofilm metabolic activity, being significantly more effective than both P3Oxysan ZS and ethanol, whose effects on metabolic activity were comparable. In conclusion, these findings highlight the importance of adapting sanitation strategies and developing standardized methods for assessing biocide susceptibility that consider the specific properties and behavior of biofilms
Evaluation of forced postures using artificial intelligence
No full textMagistritöö
Ergonoomika õppekavalTöökeskkonna füsioloogilistest ohuteguritest tulenevate terviseriskide hindamine on oluline töötajate tervise ja tööohutuse tagamisel, kuid traditsioonilised hindamismeetodid on ajamahukad ja sõltuvad hindaja subjektiivsest hinnangust. Viimastel aastatel on hakatud uurima tehisaru rakendamise võimalusi tööohutuse hindamisel, pakkudes uut lähenemisviisi riskide tuvastamiseks ja ennetamiseks. Magistritöö eesmärk oli luua juhis tehisaru kasutamiseks töökeskkonna füsioloogilistest ohuteguritest lähtuva terviseriski hindamisel. Töös analüüsiti teadus- ja arvamusartikleid, viidi läbi küsitlus ergonoomide ja töökeskkonnaspetsialistide seas ning viidi läbi ka kasutusuuring tehisaru rakenduste kohta, võrreldes nende hindamistulemusi spetsialistide omadega. Töö tulemustena toodi esile tehisaru eelised, nagu andmeanalüüsi kiirus, riskide varajane tuvastamine ja pidev jälgimine, kuid ka puudused, sealhulgas vajadus andmekaitse ja eetiliste põhimõtete järgimise järele. Spetsialistid suhtuvad tehisaru kasutamisse positiivselt, kuid rõhutavad inimliku kontrolli ja usaldusväärsuse tähtsust. Kasutusuuring näitas, et tehisaru rakendused võimaldavad täpseid ja kiireid hindamistulemusi, olles potentsiaalseks tööriistaks tööohutuse täiustamisel, kuid nõuavad veel kasutajate harjumist ja täiendavat arendust. Edasised uuringud võiksid keskenduda tehisaru rakenduste täiustamisele spetsiifiliste töötingimuste jaoks ning nende integreerimisele tööohutuse juhtimissüsteemidesse.The assessment of health risks arising from physiological hazards in the work environment is a critical component in ensuring employee health and occupational safety. However, traditional assessment methods are often time-consuming and reliant on the subjective judgment of the evaluator. In recent years, the potential for integrating artificial intelligence into occupational safety assessments has garnered increasing attention, offering a novel approach to risk identification and prevention. The objective of this master’s thesis was to develop a guideline for the application of artificial intelligence in the assessment of health risks associated with physiological hazards in the work environment. To achieve this, the study involved a systematic analysis of scientific and opinion articles, a survey conducted among ergonomists and occupational safety specialists, and a usability study of artificial intelligence applications, comparing their assessment outcomes with those of human experts. The findings highlighted several advantages of artificial intelligence, including rapid data analysis, early risk detection, and continuous monitoring, while also identifying limitations such as the need for compliance with data protection regulations and ethical considerations. Specialists expressed a generally positive attitude toward the use of artificial intelligence, emphasizing, however, the necessity of human oversight and the importance of ensuring reliability. The usability study demonstrated that artificial intelligence applications are capable of providing accurate and efficient assessment results, representing a promising tool for enhancing occupational safety, though further user adaptation and technological development are required. Future research should focus on refining artificial intelligence applications for specific working conditions and advancing their integration into occupational safety management systems
The impact of photographic parameters on the quality of photogrammetric model
No full textBakalaureusetöö
Geodeesia, kinnisvara- ja maakorralduse õppekavalFotogramm-meetriliste 3D mudelite kvaliteet sõltub suuresti lähtefotode omadustest, mida omakorda mõjutavad kaamera pildistamisparameetrid – ISO, säriaeg ja ava suurus. Kuigi kaamera seadistusi on varasemates uuringutes sageli mainitud, on nende mõju fotogramm-meetrilise mudeli kvaliteedile seni süstemaatiliselt uuritud peamiselt staatiliste kaamerate puhul, mitte mehitamata õhusõidukiga (MÕS) kogutud andmete kontekstis. Bakalaureusetöö eesmärk oli analüüsida, kuidas nende parameetrite muutmine MÕSi kaameral muudab fotogramm-meetriliste mudelite kvaliteeti.
Uurimistöö objekt asus endisel Raadi sõjaväelennuväljal. Objektile märgiti GNSS vastuvõtjaga 10 maapealset kontroll- ja 5 testpunkti ning teostati mudelite loomiseks 12 fotogramm-meetrilist lendu. Üks lend keskendus kaamera automaatseadetega piltide kogumisele, kuue lennuga koguti pilte ISO parameetrit suurendades ning viie lennuga koguti säriaja ja kaamera ava parameetreid uurivaid pilte. Fotogramm-meetrilised mudelid loodi programmis Pix4Dmapper ja mudelite kvaliteedi hindamiseks kasutati visuaalset vaatlust ja programmis genereeritud kvaliteediaruandeid.
Visuaalselt parim mudel saadi kaamera automaatseadetega tehtud piltidest. Leiti, et kaamera ISO parameeter mõjutab mudeli kvaliteeti oluliselt rohkem, kui säriaeg ja kaamera ava. Suurenenud ISO väärtus tõstab küll sensori valgustundlikkust, kuid samal ajal tekitab piltides rohkem digitaalset müra. Siiski leiti, et ka suure müraga piltidest oli maapealseid kontrollpunkte kasutades võimalik genereerida testpunktide suhtes geomeetriliselt täpne mudel.
Säriaja ja ava suuruse mõju uurivatel mudelitel oli võrreldes teistega piltidel rohkem võtme- ja sõlmpunkte, see-eest oli ISO parameetrit uurivatel mudelitel keskmine mudeli punktitihedus ühe kuupmeetri kohta suurem. Kõige tihedama punktipilve andis automaatseadetega loodud mudel. Mida ekstreemsemaks muutus kaamera parameeter, seda rohkem langes mudeli kvaliteet. Parim mudeli tuli kõige madalama võimaliku ISOga tehtud piltidest ja ISO 100 osutus katses isegi talvise pimeda ilmaga sobivaks.
Selles töös katsetati ka ekstreemseid kaamera seadistusi, et hinnata, millises ulatuses on võimalik madala pildikvaliteediga lähteandmetest koostada fotogramm-meetriline mudel, mis säilitaks piisava katvuse ja geomeetrilise täpsuse. Edasised uuringud võiksid keskenduda realistlikematele pildistusoludele, kus kaamera seadistusi varieeritakse vahemikus, mis jääb lähedale automaatika poolt soovitatud väärtustele.The quality of photogrammetric 3D models largely depends on the characteristics of the source images, which are in turn influenced by key photographic parameters such as ISO, shutter speed, and aperture size. Although camera settings are frequently mentioned in previous studies, their impact on the quality of photogrammetric models has so far been systematically examined mainly in the context of static cameras, not with data collected using unmanned aerial vehicles (UAVs). The aim of this bachelor’s thesis was to analyze how adjusting these parameters on a UAV-mounted camera affects the quality of photogrammetric models.
The study area was located at the former Raadi military airfield. Ten ground control points and five check points were marked using a GNSS receiver, and a total of 12 photogrammetric UAV flights were conducted to generate the models. One flight was performed using the camera’s automatic settings, six flights involved systematically increasing the ISO value, and five flights tested the effects of varying shutter speed and aperture size. The photogrammetric models were created using Pix4Dmapper software, and their quality was evaluated through visual inspection and software-generated quality reports.
The visually highest-quality model was obtained from images captured with automatic camera settings. It was found that the ISO setting had a significantly greater impact on model quality than shutter speed or aperture. Although higher ISO increases sensor sensitivity to light, it also introduces more digital noise into the images. Nevertheless, it was shown that even noisy images could be used to generate a geometrically accurate model when supported by ground control points.
Models testing shutter speed and aperture generally contained more key and tie points per image, while models created under varying ISO settings exhibited higher average point density per cubic meter. The densest point cloud was produced by the model based on automatically captured images. In general, the more extreme the camera setting, the more the model’s quality deteriorated. The best-performing model was generated from images taken at the lowest possible ISO value — ISO 100 — which proved suitable even in the low-light conditions of a winter setting.
This study also included tests using extreme camera settings to determine the extent to which low-quality images can still produce models with acceptable coverage and geometric accuracy. Future research should focus on more realistic image acquisition scenarios, where camera settings are adjusted within a range close to those suggested by the automatic system