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Performance comparison and real-time responsiveness analysis of IEC 61131-3 and IEC 61499 runtime environments - A case study of Beremiz, OpenPLC, and EcoRT
No full textThe increasing complexity of industrial automation systems under Industry 4.0 has raised the demand for control solutions with both high execution efficiency and reliable real-time responsiveness. IEC 61131-3 and IEC 61499 are two prominent standards for industrial control systems, each supported by a variety of runtime environments (RTEs). This thesis conducts a comprehensive empirical study to compare representative RTEs from both standards, Beremiz and OpenPLC for IEC 61131-3, and EcoRT for IEC 61499. Functionally equivalent application programs with varying computational loads are deployed on these RTEs to assess their execution latency. In addition, analytical models are constructed to evaluate their response time under both time-triggered and event-triggered input conditions. Experimental results demonstrate notable differences in execution efficiency and real-time responsiveness among RTEs. Furthermore, the analysis highlights the performance advantages of IEC 61499 in event driven scenarios due to its decoupled I/O and event-driven execution. The findings contribute to a deeper understanding of runtime behavior under different standards and provide a universal framework for modeling and analyzing real-time responsiveness in PLC systems
The role of a leader’s emotional intelligence in crisis leadership
No full textTässä tutkielmassa tarkasteltiin, millainen rooli johtajan tunneälyllä on kriisijohtamisessa. Tutkielma toteutettiin kirjallisuuskatsauksen muodossa hyödyntäen erilaisia tutkimuksia ja tieteellisiä artikkeleja.
Tutkielmassa käsittelin tunneälyn taustaa sekä sen määritelmää ja vaikutuksia. Tutustuin myös kriisien ja kriisijohtamisen määritelmiin sekä erilaisiin rajauksiin ja teorioihin, joiden avulla kriisijohtamista tarkastellaan. Lisäksi tarkastelin kriisijohtamisessa korostuvia tehtäviä. Kokosin yhteen tunneälyn ja kriisijohtamisen aiheet tarkastelemalla niiden keskinäistä suhdetta tutkimuskysymykseni avulla: Mikä on johtajan tunneälyn rooli kriisijohtamisessa?
Tutkielmassani ilmeni, että tunneälyllä on positiivisia vaikutuksia ihmistenvälisissä tehtävissä. Näitä tehtäviä ovat esimerkiksi vuorovaikutus ja viestintä sekä työntekijöiden tukeminen ja motivointi. Lisäksi tunneälyn vaikutukset osoittautuivat myönteiseksi myös johtajalle itselleen. Johtaja hyötyy tunneälystä esimerkiksi päätöksenteossa sekä vaikeiden tunteiden käsittelyssä
Miehittämätön lumivyörypelastus
No full textThe use of unmanned aerial vehicles (UAVs) fitted with Software-Defined Radios (SDRs) for avalanche rescue operations is investigated in this thesis. The goal of the project is to provide a rescue solution that is both accessible and flexible by utilizing commercially available open-source hardware and software. By detecting and localizing 457 kHz avalanche beacon signals on its own, the system increases search efficiency while lowering the risks to human rescuers. The findings show the potential of open technology in crucial emergency applications by showing that open-source UAV-SDR integration offers an affordable, adaptable, and dependable method of avalanche victim localization.Tämä diplomityö tutkii ohjelmistoradiolla (SDR) varustettujen miehittämättömien ilma-alusten (UAV) käyttöä lumivyörypelastustehtävissä. Hyödyntämällä kaupallisesti saatavilla olevaa avoimen lähdekoodin laitteistoa ja ohjelmistoa tutkimuksen tavoitteena on kehittää saavutettava ja mukautuva pelastusratkaisu. Järjestelmä havaitsee ja paikantaa 457 kHz:n lumivyörylähetinsignaalit itsenäisesti parantaen etsintätehokkuutta ja vähentäen ihmispelastajiin kohdistuvia riskejä. Tulokset osoittavat, että avoimen lähdekoodin UAV-SDR-integraatio tarjoaa kustannustehokkaan, joustavan ja luotettavan lähestymistavan lumivyöryuhrien paikantamiseen, korostaen avoimien teknologioiden käyttömahdollisuuksia kriittisissä hätätilanteissa
Plasma flows and turbulence in gyrokinetic simulations
No full textOne of the primary challenges in the nuclear fusion research is comprehending and controlling plasma turbulence in fusion reactors. With the advancement of computational power in recent years, gyrokinetic codes have emerged as pivotal tools in elucidating the mechanisms underlying plasma turbulence. This thesis presents the utilization of two gyrokinetic codes, ELMFIRE and Gyrokinetic Electromagnetic Numerical Experiment (GENE), to investigate plasma turbulence in the core and edge regions of the Fisichiskii Tokamak-2 (FT-2) tokamak.
To more comprehensively predict the scrape-off layer physics in the FT-2 tokamak, several code changes are implemented in ELMFIRE to recycle the particles exiting the simulation domain in the toroidal direction closer to the poloidal limiters in FT-2. Using radial particles source profiles from ASTRA simulations along with recycling plasma ions and electrons closer to the limiters exhibited qualitative agreement of the electron density profiles within 30% of the profiles measured by Langmuir probes. However, the electron temperature profiles are predicted systematically higher by a factor of 1.5 to 2 with the respective Langmuir probe measurement, still within the uncertainties of measurements.
Using the GENE code, the Geodesic acoustic mode (GAM) intermittency in the core of FT-2 is studied by performing a global non-linear simulation. The simulation results revealed intermittency in GAMs close to the loworder rational surface (q=3). This finding constitutes the first observation of GAM intermittency in a gyrokinetic simulation. The underlying cause of this GAM intermittency is attributed to the non-linear coupling between GAMs and turbulence at this radial location. Furthermore, the density fluctuations exhibited intermittency at the same radial location, confirming the non-linear coupling between GAMs and turbulence.
The impact of the Krook-type source operators on the GAM dynamics in the GENE simulations is investigated. Global non-linear simulations showed that the GAM amplitude increases with increasing Krook-type source operator values, driven by an increased GAM drive. The zonal flows amplitude decreases with the increasing value of the Krook-type source operators in the center region. Notably, the GAM damping in the center region increases by 15 to 100% with increasing operator values. Despite the GAMs exhibiting intermittency, their quiescent and active periods differ with operator values
Kamerapohjaiset syvyysestimaatiotekniikat puhelimissa
No full textÄlypuhelimet ovat nykyään hyvin yleisiä ja niiden kameroita hyödynnetään moniin tarkoituksiin. Perinteisen kuvaamisen lisäksi niitä voidaan käyttää syvyysestimaatiossa, jossa kuvan jokaisen pikselin etäisyys kamerasta arvioidaan. Syvyysestimaation avulla voidaan parantaa lisätyn todellisuuden (AR) sovelluksia ja lisätä todenmukainen sumennus muotokuvaa otettaessa. Syvyysestimaatioon puhelimella liittyy kuitenkin haasteita. Erityisesti haasteena on puhelimen rajallinen suorituskyky ja usein puuttuvat edistyneet syvyyssensorit. Tämän kandidaatintyön tavoitteena on antaa yleisesittely puhelimissa olevista syvyysestimaatiotekniikoista ja vertailla tekniikoiden soveltuvuutta aiemmin mainituissa käyttökohteissa. Työssä esitellään syvyysestimaation perusteet sekä menetelmien jaottelu aktiivisiin ja passiivisiin tekniikoihin.
Työ on kirjallisuuskatsaus, jossa käydään läpi yleisimpien syvyysestimaatiotekniikoiden toimintaperiaatteet ja vertaillaan niiden vahvuuksia ja heikkouksia. Työssä keskitytään erityisesti passiivisiin tekniikoihin, jotka toimivat yhden tai kahden kameran avulla. Niistä käydään läpi tekniikat, jotka perustuvat stereokameroihin, syvyys liikkeestä -menetelmään, neuroverkkoihin ja Dual Pixel -sensoriin. Lisäksi käydään lyhyesti läpi aktiivisia tekniikoita, jotka käyttävät erillisiä projektoreita ja sensoreita. Aktiivisista tekniikoista käsitellään LiDAR, ToF-kamerat ja strukturoitu valo.
Kirjallisuuskatsauksen perusteella todetaan, että aktiiviset tekniikat mahdollistavat tarkan ja pimeässä toimivan syvyysestimaation, mutta vaativat erillisiä laitteistoja, joita löytyy vain tietyistä kalliimmista puhelimista. Passiiviset tekniikat taas käyttävät ainoastaan puhelimen kameroita, mutta vaativat valoisuutta ja osa tekniikoista toimivat huonosti tekstuurittomilla alueilla kuten valkoisilla seinillä. Eri passiivisilla tekniikoilla on omat haasteensa. Esimerkiksi stereokamerat vaativat toimiakseen kaksi kameraa, syvyys liikkeestä -tekniikka vaatii puhelimen liikkeen, neuroverkot saattavat toimia huonosti eri ympäristöissä ja Dual Pixel -kameraan perustuvan tekniikan käyttöetäisyys on lyhyt.
Johtopäätöksenä todetaan, että passiivisen syvyysestimaatiotekniikan valinta riippuu suurelta osin käyttötarkoituksesta ja puhelimessa saatavilla olevista kameroista. Yhdistämällä tekniikoita voidaan saavuttaa entistä parempia tuloksia ja erityisesti neuroverkot tulevat mahdollistamaan uusia mobiilisovelluksia
Utilizing mobile phone tracking data to estimate Intra-City modal mobility : A study on active mobility in two Finnish City regions
No full textPublisher Copyright: © 2025 The AuthorsUnderstanding sustainable and active mobility in urban areas is essential for promoting healthier, low-carbon city planning. While previous research has utilized a wide range of data sources and spatial scales, there has been minimal focus on modal detection within urban areas. This analysis utilizes mobile phone tracking data to estimate travel modes and analyse modal mobility patterns at the intra-urban scale in Finland's Greater Helsinki region and Oulu. The origin-destination matrix containing travel volumes is coupled with the accessibility network to infer estimated modes based on travel times. To account for instances of overlapping trip times or short trips that are difficult to quantify, a filter based on both trip time and length comparison is applied to the dataset. The share and spatial distribution of active mobility modes such as walking, cycling as well as public transport are analysed to explore their relationship with urban form and travel behaviour. The proposed method provides a novel way to detect transport hubs and areas with high active and public transport use, corresponding to inner urban areas. The proportion of transport modes detected in the study provides a reasonable estimate the amount reported in the National Transport Survey of the same year. These insights aim to inform sustainable urban planning, promote healthier mobility choices, and support policies that enhance carbon neutrality and climate resilience.Peer reviewe
Optimal Graph Information Fused Graph Attention Network for Traffic Flow Forecasting
No full textTo manage and make decisions about intelligent transportation systems more efficiently, accurate traffic flow forecasting is necessary. Traffic flow forecasting has complex spatial correlation and time dependence. Most current research models are based on a predefined graph structure with a priori knowledge for prediction, which cannot well extract the hidden spatial relationships in traffic data. In this paper, we propose the Optimal Graph Information Fused Graph Attention Network (OGIF-GAT). Specifically, we learn the actual connections between nodes and the hidden spatial relationships through the multigraph feature fusion structure. Next, we design a new graph attention network (GAT), which improves the problem of ignoring edge features in the graph structure in the traditional GAT model and considers their edge features when estimating the correlation of each neighboring node pair: the effect that the distance factor between neighboring nodes has on the spatial correlation. In addition, we use the temporal hybrid transformer (THT) to learn temporal dependencies. Extensive experiments on four public transportation datasets (PeMS04, PeMS08, PeMS-BAY, and METR-LA) demonstrate that our model achieves the optimal level of traffic flow prediction accuracy on all of them and is shown to have strong generalization ability. Compared to STSGCN, the mean absolute error (MAE) decreases by 7.9%, 10.3%, 33.2%, and 19.6%, respectively.Peer reviewe
Enhancing Oxygen Reduction Kinetics and Proton Transfer of La0.6Sr0.4Co0.2Fe0.8O3−δ Cathode through Pr2Ni0.5Co0.5O4−δ Impregnation for Protonic Ceramic Fuel Cells
No full textPublisher Copyright: © 2024 The Author(s). Advanced Energy Materials published by Wiley-VCH GmbH.Sluggish reaction kinetics in oxygen reduction reaction (ORR) is one of the most important challenges to the development of protonic ceramic fuel cells (PCFCs). La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) exhibits high mixed ionic–electronic conductivity in traditional solid oxide fuel cells, but their slow proton transfer and ORR kinetics impedes practical applications. Herein, composite Pr2Ni0.5Co0.5O4−δ (PNC) particles composed of a perovskite PrNi0.5Co0.5O3−δ phase and a PrO2 phase are impregnated into a LSCF cathode to enhance the ORR activity and proton transfer. The polarization tested in a symmetric cell with PNC-impregnated LSCF cathode is 0.06 Ω cm2 at 700 °C. The fuel cell with this impregnated cathode shows maximum power densities of 1857 mW cm−2 at 700 °C. Moreover, the impregnated cathode exhibits a low degradation rate in the durability test. This work not only provides a novel and practical approach to improving the performance of current cathode materials for PCFCs but also highlights the potential for enhancing the commercial viability of PCFC technology.Peer reviewe
Signalointi ja epänormaalit tuotot: analyysi suomalaisista avoimen markkinan omien osakkeiden takaisinostoista
No full textThis thesis examines the stock performance of Finnish firms following open market share repurchase initiations from 2006 to 2021, using signalling theory as the primary interpretive framework. I find that repurchasing firms earn an average short-term abnormal return of approximately 1.2% over a five-day window around the initiation. Over the following two years, they outperform by a compounded abnormal return of around 5%, depending on the used benchmark. Contrary to expectations, this outperformance disappears by years three and four. This pattern suggests that the information conveyed by repurchase initiations is not immediately reflected in prices, but instead incorporated gradually as investors gain confidence in the signal
Design for Reuse: The Impact of Initial Clothing Design Choices on Reuse Potential in Finland's Second-Hand Market
No full textThe second-hand clothing market is predicted to continue growing in the coming years. At the same time, post-consumer waste generated by overconsumption and overproduction in the fashion industry remains a concerning issue. This thesis investigates how fashion design can enhance clothing reuse within the second-hand market, aiming to support circularity in the fashion industry. While the environmental and social impacts of fashion production are gaining the attention of researchers, manufacturers, and consumers, the reuse of garments offers a promising intervention point that has not been deeply explored in the reviewed literature.
This study is positioned in the context of the Finnish second-hand online clothing market, due to the high level of maturity and potential growth of this industry. Focusing on the reuse phase of the garment lifecycle, the research explores how initial design choices impact a product's potential to be resold and reused. The aim is to identify what elements and designers should focus on to improve the potential of clothing being resold and reused. Following this, the thesis reviewed literature from three different streams to frame the research: design for longevity, second-hand consumption, and consumer motivations and needs. The study adopts a qualitative research approach through semi-structured interviews with two groups of experts in this field: Circularity Experts and SHC Resale Professionals. Based on the data insights, four key themes emerged as relevant to addressing the reuse phase within the design process: Quality, User-Centric Design, Aesthetic Appeal, and Life-Cycle Awareness. These themes include design elements and strategies that may potentially prolong garment circulation, specifically during the reuse phase, influencing their potential to be resold.
Based on the findings, this research reflects on the practical implications for designers, brands, and resale professionals aiming to integrate reuse considerations into product development. This becomes increasingly important given the current shift in legislation and growing pressure for a more sustainable industry in the EU. The research also contributes to current and future research examining second-hand clothing market from a design perspective, as well as approaches to designing for clothing circulation