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Analysis of bar forces in a statically determinate truss
No full textKandinaattityön aiheena on staattisesti määrätyn ristikon sauvavoimien analysointi. Työn tavoitteena on tutustua erilaisiin sauvavoimien laskentamenetelmiin ja vertailla niiden avulla saatuja tuloksia.
Työ sisältää esimerkkitapauksen perinteisestä kattoristikosta, johon kohdistuu erilaisia kuormia. Esimerkkitapauksessa rakenteelle luodaan murtorajatila STR mukaiset kuormitusyhdistelmät. Jokainen tapaus lasketaan useilla eri menetelmillä. Tulokset taulukoidaan ja niitä vertaillaan laskentamenetelmittäin. Tuloksista huomataan, että kaikki menetelmät tuottivat keskenään yhteneviä tuloksia ja erot ovat marginaalisia.
Aineistoa on kerätty internetistä ja kirjastoista. Työssä käytetään useita eri ohjelmistoja visualisoimaan muun muassa teoriaa ja kuormitustapauksia
Understanding tree growth dependencies using multisensorial point clouds
No full textAbstract
Individual tree crowns are the primary interface with the environment and closely relate to tree growth, yet accurately characterizing them remains challenging. This study aimed to understand how individual tree stem volume growth (ΔV) depends on crown metrics both at the beginning of the monitoring period (T1_C) and on their changes over time (ΔC), using close-range multisensorial point clouds obtained from terrestrial and airborne laser scanning (TLS and ALS). Data were collected from 22 sample plots in boreal forests of Finland in 2014 (T1) and 2021 (T2). Spearman’s rank correlation coefficient (ρ) was employed to assess the relationships between ΔV and crown metrics across different tree species. Additionally, Random Forest regression (RF) was applied to explore the relative importance of these metrics in explaining ΔV. A strong correlation (ρ = 0.60–0.63) was found between ΔV of Scots pine (Pinus sylvestris L.) and crown metrics, including volume (T1_CV), perimeter (T1_CP), projection area (T1_CA2D), and top height (T1_CHmax). In contrast, ΔV of Norway spruce (Picea abies (L.) H. Karst.) showed only weak correlations, with the best metrics being crown base height (T1_CHmin), T1_CV, and its change (ΔCV) (ρ = 0.32–0.38). For birches (Betula sp.), ΔV also exhibited weak correlations (ρ = 0.27–0.34), mainly with crown surface area (T1_CA3D), ΔCV, and T1_CHmax. RF analyses further highlighted species-specific drivers of ΔV. Scots pine with the most important metric of T1_CHmax explained 50% of variation in ΔV. However, ΔCV was the most important metric in explaining ΔV of Norway spruce and birch, with explained variability of 20% and 6%, respectively. In conclusion, this study demonstrated that multisensorial point clouds provide an effective approach to analyze the relationship between ΔV and tree crown structure. Nevertheless, challenges persist in consistently measuring various crown metrics over time and distinguishing actual changes from measurement errors.Abstract
Individual tree crowns are the primary interface with the environment and closely relate to tree growth, yet accurately characterizing them remains challenging. This study aimed to understand how individual tree stem volume growth (ΔV) depends on crown metrics both at the beginning of the monitoring period (T1_C) and on their changes over time (ΔC), using close-range multisensorial point clouds obtained from terrestrial and airborne laser scanning (TLS and ALS). Data were collected from 22 sample plots in boreal forests of Finland in 2014 (T1) and 2021 (T2). Spearman’s rank correlation coefficient (ρ) was employed to assess the relationships between ΔV and crown metrics across different tree species. Additionally, Random Forest regression (RF) was applied to explore the relative importance of these metrics in explaining ΔV. A strong correlation (ρ = 0.60–0.63) was found between ΔV of Scots pine (Pinus sylvestris L.) and crown metrics, including volume (T1_CV), perimeter (T1_CP), projection area (T1_CA2D), and top height (T1_CHmax). In contrast, ΔV of Norway spruce (Picea abies (L.) H. Karst.) showed only weak correlations, with the best metrics being crown base height (T1_CHmin), T1_CV, and its change (ΔCV) (ρ = 0.32–0.38). For birches (Betula sp.), ΔV also exhibited weak correlations (ρ = 0.27–0.34), mainly with crown surface area (T1_CA3D), ΔCV, and T1_CHmax. RF analyses further highlighted species-specific drivers of ΔV. Scots pine with the most important metric of T1_CHmax explained 50% of variation in ΔV. However, ΔCV was the most important metric in explaining ΔV of Norway spruce and birch, with explained variability of 20% and 6%, respectively. In conclusion, this study demonstrated that multisensorial point clouds provide an effective approach to analyze the relationship between ΔV and tree crown structure. Nevertheless, challenges persist in consistently measuring various crown metrics over time and distinguishing actual changes from measurement errors
Multiagent Path Planning With Neural Obstacle Avoidance for Autonomous Heavy Trucks
No full textAbstract
Autonomous trucks in busy port terminals must navigate narrow aisles, tight corners, and frequent interactions with multiple vehicles while maintaining both safety and efficiency. This paper presents a hierarchical multiagent navigation framework that integrates an enhanced grid-based Theta∗ global planner with obstacle inflation and clearance-aware costs, an artificial potential field (APF)–based local controller augmented by lightweight neural correction, and a simple coordination protocol for resolving intertruck conflicts. We evaluate the approach in a high-fidelity Unity digital twin of the Port of Oulu using two traffic scenes with three trucks executing simultaneous tasks. Experiments are repeated under identical initial conditions with independent random perturbations to capture run-to-run variability, and results are reported as the mean ± standard deviation. We compare the proposed Theta∗-based planner with a standard grid-based A∗ baseline and an 8-neighborhood A∗ variant under the same occupancy grid, obstacle inflation, and curvature constraints to isolate the impact of expanded action sets within the A∗ framework. A greedy heuristic baseline is also included in the simpler scene, where it can complete scheduling. Across trucks, Theta∗ achieves 43.0% lower travel time and 39.4% fewer avoidance events than A∗ in the dense-yard scene and 59.5% lower travel time and 91.4% fewer avoidance events in the gate–yard scene, while also improving a combined tracking-accuracy index by 22.1% and 12.7%, respectively. Path-tracking evaluation shows stable mean errors (average mean lateral deviation ≈ 0.40 m and mean heading error ≈ 1.69° across trucks), with transient peaks mainly occurring at high-curvature segments, narrow-clearance passages, and interaction-driven maneuvers. We further include a time-bounded scalability study by increasing the local fleet size to assess the coordination overhead under denser intertruck interactions. These results indicate that clearance-aware any-angle planning, together with neural-tuned local avoidance and lightweight coordination, can improve both efficiency and execution quality for port–yard truck autonomy.Abstract
Autonomous trucks in busy port terminals must navigate narrow aisles, tight corners, and frequent interactions with multiple vehicles while maintaining both safety and efficiency. This paper presents a hierarchical multiagent navigation framework that integrates an enhanced grid-based Theta∗ global planner with obstacle inflation and clearance-aware costs, an artificial potential field (APF)–based local controller augmented by lightweight neural correction, and a simple coordination protocol for resolving intertruck conflicts. We evaluate the approach in a high-fidelity Unity digital twin of the Port of Oulu using two traffic scenes with three trucks executing simultaneous tasks. Experiments are repeated under identical initial conditions with independent random perturbations to capture run-to-run variability, and results are reported as the mean ± standard deviation. We compare the proposed Theta∗-based planner with a standard grid-based A∗ baseline and an 8-neighborhood A∗ variant under the same occupancy grid, obstacle inflation, and curvature constraints to isolate the impact of expanded action sets within the A∗ framework. A greedy heuristic baseline is also included in the simpler scene, where it can complete scheduling. Across trucks, Theta∗ achieves 43.0% lower travel time and 39.4% fewer avoidance events than A∗ in the dense-yard scene and 59.5% lower travel time and 91.4% fewer avoidance events in the gate–yard scene, while also improving a combined tracking-accuracy index by 22.1% and 12.7%, respectively. Path-tracking evaluation shows stable mean errors (average mean lateral deviation ≈ 0.40 m and mean heading error ≈ 1.69° across trucks), with transient peaks mainly occurring at high-curvature segments, narrow-clearance passages, and interaction-driven maneuvers. We further include a time-bounded scalability study by increasing the local fleet size to assess the coordination overhead under denser intertruck interactions. These results indicate that clearance-aware any-angle planning, together with neural-tuned local avoidance and lightweight coordination, can improve both efficiency and execution quality for port–yard truck autonomy
Maintenance development : from traditional diagnostics to data-based prognostics
No full textKandidaatintyö tarkastelee kunnonvalvonnan kehitystä perinteisistä kunnonvalvonnan menetelmistä modernimpiin ennakoiviin kunnonvalvonnan järjestelmiin ja sitä, mitä muutoksia se tuo mukanaan. Työssä käydään läpi erilaiset menetelmät diagnostiikasta, niiden käyttökohteita sekä minkälaisia vahvuuksia niillä on. Työssä arvioidaan myös sitä, miten ennakoivalla kunnonvalvonnalla saadaan tuotettua lisäarvoa suhteessa perinteisiin menetelmiin.
Kunnonvalvonnan muutokset kytkeytyvät vahvasti digitalisaatioon, lisääntyneeseen datan keräämiseen sekä sen hyödyntämiseen päätöksenteossa. Työssä tulee ilmi, että kunnonvalvonnan kehitys tarkoittaa käytännössä päätöksenteon laadun paranemista.
Työ on toteutettu kirjallisuuskatsauksena ja sen lähteitä on etsitty pääasiassa internetistä. Työn tavoite on muodostaa kokonaiskuva kunnonvalvonnan kehityssuunnasta ja sen keskeisistä ratkaisuista. Se tuottaa tietoa siitä, mitä haasteita uusien menetelmien kanssa voi olla ja miten uusia järjestelmiä hyödynnetää
Association of Seroprevalence of Respiratory Pathogens and Herd-Level Management Factors with Inflammatory Markers in Dairy Cattle
No full textAbstract
This cross-sectional study investigated the associations between the acute-phase proteins (APP) serum amyloid A (SAA) and haptoglobin (Hp), herd-level factors, and the seroprevalence of respiratory pathogens in Estonian dairy herds. Serum samples were analysed from 938 cows (95 herds) and 921 heifers (94 herds). Seroprevalence was tested for bovine herpesvirus 1 (BHV-1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3, bovine viral diarrhoea virus, bovine coronavirus, bovine adenovirus, and Mycoplasma bovis (M. bovis). Farm visits included questionnaires on herd management practices. Linear random-intercept regression models showed higher serum SAA concentrations in cows from farms with BHV-1 seroprevalence of >50% and on BRSV-positive farms (p < 0.05), while farms employing a veterinarian had lower serum SAA concentrations. Cows had higher serum Hp concentrations in M. bovis-positive herds (p = 0.030). In heifers, serum SAA concentrations increased with low to moderate BHV-1 seroprevalence, decreased with higher M. bovis seroprevalence, and were higher in free-stall or mixed housing compared to tie-stall housing. Heifers’ serum Hp concentrations were lower in BHV-1-positive herds, but higher in herds with breeding bulls and larger herd sizes. To conclude, APP may reflect the herd health status and management-related effects on animals, supporting their use in herd-level monitoring.Abstract
This cross-sectional study investigated the associations between the acute-phase proteins (APP) serum amyloid A (SAA) and haptoglobin (Hp), herd-level factors, and the seroprevalence of respiratory pathogens in Estonian dairy herds. Serum samples were analysed from 938 cows (95 herds) and 921 heifers (94 herds). Seroprevalence was tested for bovine herpesvirus 1 (BHV-1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3, bovine viral diarrhoea virus, bovine coronavirus, bovine adenovirus, and Mycoplasma bovis (M. bovis). Farm visits included questionnaires on herd management practices. Linear random-intercept regression models showed higher serum SAA concentrations in cows from farms with BHV-1 seroprevalence of >50% and on BRSV-positive farms (p < 0.05), while farms employing a veterinarian had lower serum SAA concentrations. Cows had higher serum Hp concentrations in M. bovis-positive herds (p = 0.030). In heifers, serum SAA concentrations increased with low to moderate BHV-1 seroprevalence, decreased with higher M. bovis seroprevalence, and were higher in free-stall or mixed housing compared to tie-stall housing. Heifers’ serum Hp concentrations were lower in BHV-1-positive herds, but higher in herds with breeding bulls and larger herd sizes. To conclude, APP may reflect the herd health status and management-related effects on animals, supporting their use in herd-level monitoring
Economically viable population-based interventions to promote physical activity behavior based on a systematic review
No full textAbstract
Objective:
Physical inactivity contributes to substantial public health and economic burdens. This study reviews the cost-effectiveness of population-based physical activity interventions. The literature search focused on studies that have successfully promoted physical activity behavior based on valid measurement.
Methods:
The systematic literature search was conducted across five electronic databases in January 2021. To facilitate comparison between studies, the results on effect size and cost-effectiveness (incremental cost-effectiveness ratio, ICER) were harmonized.
Results:
All five studies included in this review were trial-based economic evaluations, of which two studies modeled long-term cost-effectiveness. The included studies were mainly print-based interventions, and their ICER values ranged from 0.15 to 4.14 US (2024) per metabolic equivalent of task hour gained (including only intervention costs). The most economically viable intervention utilized computer-tailored physical activity advice in the general population, while three interventions targeted inactive adults.
Conclusions:
Only a few intervention studies showed positive effects on physical activity behavior and evaluated their cost-effectiveness at the population level. Future studies should consider accurate cost calculations and reporting, high-quality methods for measuring physical activity behavior, and inter-individual variations. Moreover, unified standardized methods for determining the cost-effectiveness of physical activity interventions are needed
Changes in leisure time physical activity, obesity-related morbidities, fatal and non-fatal CVD events and total mortality: Over 20-year follow-up in the opera study
No full textAbstract
Background:
The impact of changes in leisure time physical activity (LTPA) is not well-documented, especially when considering occupational physical activity (OPA). This study examines the effects of LTPA changes in workers with varying physical activity demands.
Methods:
Part of the OPERA study, we tracked morbidities for over 20 years (P1, from 1993 to 2014) and mortality for over 8 years (P2, from 2014 to 2021–2022) with 599 participants. They were categorized into four LTPA groups (“sedentary,” “started,” “quit,” “active”) and two OPA groups (“office workers” and “occupationally physically active”).
Results:
Maintaining regular LTPA was associated with lower incidence of hypertension, diabetes and metabolic syndrome (p-values 0.007, < 0.001 and <0.001 respectively). Non-fatal cardiovascular disease (CVD) events were more common (p = 0.006, HR 1.99, CI95% 1.22–3.26) in the “quit” group during P1, especially among “occupationally physically active” (p < 0.001, HR 2.29, CI95% 1.23–4.29). During P2, fatal CVD events were associated with being in the “sedentary” group (p = 0.042, HR 2.67, CI95% 1.04–7.03). This association was particularly evident among “office workers,” where belonging to the “sedentary” and “quit” groups was associated with a higher risk of fatal CVD events (p = 0.017, HR 5.45, CI95%1.36–21.91, and p = 0.025, HR 4.55, CI95% 1.21–17.19, respectively). Furthermore, total mortality was associated with being in the “sedentary” or “quit” groups (p = 0.029, HR 3.69, CI95% 1.14–11.93, and p = 0.009, HR 4.61, CI95%1.47–14.49, respectively).
Conclusions:
Stopping LTPA in middle age was associated to higher risk for non-fatal CVD events in “occupationally physically active” individuals. Fatal CVD events were associated with a sedentary lifestyle in whole study population. Among “office workers,” both a sedentary lifestyle and stopping regular LTPA were associated with higher risks of fatal CVD events and all-cause mortality.Abstract
Background:
The impact of changes in leisure time physical activity (LTPA) is not well-documented, especially when considering occupational physical activity (OPA). This study examines the effects of LTPA changes in workers with varying physical activity demands.
Methods:
Part of the OPERA study, we tracked morbidities for over 20 years (P1, from 1993 to 2014) and mortality for over 8 years (P2, from 2014 to 2021–2022) with 599 participants. They were categorized into four LTPA groups (“sedentary,” “started,” “quit,” “active”) and two OPA groups (“office workers” and “occupationally physically active”).
Results:
Maintaining regular LTPA was associated with lower incidence of hypertension, diabetes and metabolic syndrome (p-values 0.007, < 0.001 and <0.001 respectively). Non-fatal cardiovascular disease (CVD) events were more common (p = 0.006, HR 1.99, CI95% 1.22–3.26) in the “quit” group during P1, especially among “occupationally physically active” (p < 0.001, HR 2.29, CI95% 1.23–4.29). During P2, fatal CVD events were associated with being in the “sedentary” group (p = 0.042, HR 2.67, CI95% 1.04–7.03). This association was particularly evident among “office workers,” where belonging to the “sedentary” and “quit” groups was associated with a higher risk of fatal CVD events (p = 0.017, HR 5.45, CI95%1.36–21.91, and p = 0.025, HR 4.55, CI95% 1.21–17.19, respectively). Furthermore, total mortality was associated with being in the “sedentary” or “quit” groups (p = 0.029, HR 3.69, CI95% 1.14–11.93, and p = 0.009, HR 4.61, CI95%1.47–14.49, respectively).
Conclusions:
Stopping LTPA in middle age was associated to higher risk for non-fatal CVD events in “occupationally physically active” individuals. Fatal CVD events were associated with a sedentary lifestyle in whole study population. Among “office workers,” both a sedentary lifestyle and stopping regular LTPA were associated with higher risks of fatal CVD events and all-cause mortality
Roadmap for light interaction with biophotonic surfaces and their diverse applications
No full textAbstract
Significance:
Biophotonics has advanced through many discoveries, yet challenges remain, including label-free biomolecular specificity, quantitative imaging, and single-molecule detection. Progress is further constrained by the need for cheaper, lighter, miniaturized materials that still meet strict optical, electrical, and mechanical specifications. This limitation can be overcome if bioinspired structures are developed. One of the developed areas in which solutions in nature are used is micro and nanostructures including nanosurfaces. It offers a way to increase biomolecular specificity and develop lightweight, low-cost devices for biomedicine. However, it requires measuring phenomena in materials and testing these materials in applications, e.g., sensing systems.
Aim:
We offer a concise, authoritative overview of biophotonics—from nanoscale light–biomolecule interactions to bioinspired materials, phantoms, test methods, and sensor development.
Approach:
A coherent and comprehensive analysis of the crucial problems related to the development of bioinspired materials and devices was carried out. Recent advances in light scattering by biological surfaces enable structure characterization, disease diagnosis, red-blood-cell analysis, drug discovery, and optical imaging and sensing. Structural and genetic bases of biological photonic surfaces were examined, alongside key performance factors in bio-inspired materials—biocompatibility, biodegradability, structure-optics coupling (e.g., dynamic color change), and scalability limits. We survey chiral nanomaterials, silica frustules, and artificial surfaces that emulate peacock feathers, butterfly wings, iridescent fruits, plant petals, and beetle cuticles, highlighting complementary diagnostics—omics, hyperspectral, and terahertz imaging—for structural analysis and material innovation. We examine bio-inspired phantoms for medical calibration, recent advances in Monte Carlo tissue light-transport modeling, and the resulting applications of these materials and diagnostic tools.
Results:
Results confirm a broad set of tunable bio-inspired materials: key optical phenomena were mapped, structures fabricated and modeled, phantoms validated, and strong sensor potential demonstrated.
Conclusions:
We survey emerging biophotonics, review material and system requirements, and emphasize simplifying and miniaturizing sensors for biomedical use.Abstract
Significance:
Biophotonics has advanced through many discoveries, yet challenges remain, including label-free biomolecular specificity, quantitative imaging, and single-molecule detection. Progress is further constrained by the need for cheaper, lighter, miniaturized materials that still meet strict optical, electrical, and mechanical specifications. This limitation can be overcome if bioinspired structures are developed. One of the developed areas in which solutions in nature are used is micro and nanostructures including nanosurfaces. It offers a way to increase biomolecular specificity and develop lightweight, low-cost devices for biomedicine. However, it requires measuring phenomena in materials and testing these materials in applications, e.g., sensing systems.
Aim:
We offer a concise, authoritative overview of biophotonics—from nanoscale light–biomolecule interactions to bioinspired materials, phantoms, test methods, and sensor development.
Approach:
A coherent and comprehensive analysis of the crucial problems related to the development of bioinspired materials and devices was carried out. Recent advances in light scattering by biological surfaces enable structure characterization, disease diagnosis, red-blood-cell analysis, drug discovery, and optical imaging and sensing. Structural and genetic bases of biological photonic surfaces were examined, alongside key performance factors in bio-inspired materials—biocompatibility, biodegradability, structure-optics coupling (e.g., dynamic color change), and scalability limits. We survey chiral nanomaterials, silica frustules, and artificial surfaces that emulate peacock feathers, butterfly wings, iridescent fruits, plant petals, and beetle cuticles, highlighting complementary diagnostics—omics, hyperspectral, and terahertz imaging—for structural analysis and material innovation. We examine bio-inspired phantoms for medical calibration, recent advances in Monte Carlo tissue light-transport modeling, and the resulting applications of these materials and diagnostic tools.
Results:
Results confirm a broad set of tunable bio-inspired materials: key optical phenomena were mapped, structures fabricated and modeled, phantoms validated, and strong sensor potential demonstrated.
Conclusions:
We survey emerging biophotonics, review material and system requirements, and emphasize simplifying and miniaturizing sensors for biomedical use
