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Climate Impact on Electric Vehicle Energy Consumption in the Baltic Region
No full textMagistritöö
Energiakasutuse õppekavalHuvi elektrisõidukite vastu on viimastel aastatel pidevalt kasvanud, neid peetakse väiksema heitkogusega alternatiiviks sisepõlemismootoriga sõidukitele. Elektriautode laialdane levik Euroopas (ka Baltikumis) on suures osas tuginenud riiklikele toetustele ja soodustustele. Kuna nende toetuste määr on hakanud vähenema, seisab elektrisõidukite turg uute väljakutsete ees, eriti Balti riikides, kus põhjamaine kliima mõjutab oluliselt elektriautode töövõimet. Balti riikidele omased madalad temperatuurid võivad märkimisväärselt vähendada elektriautode sõiduulatust ja energiatõhusust, mõjutades seeläbi nii kasutuskulusid kui ka kasutajate rahulolu. Balti ilmastikutingimuste, eelkõige temperatuuri, mõju mõistmine elektriautode energiatarbimisele on oluline, et hinnata nende efektiivsust külmades ilmastikutingimustes. Käesoleva uuringu peamine eesmärk on hinnata muutuvate ilmastikutingimuste mõju elektrisõidukite energiatarbele ning pakkuda teavet nende energiatõhususe kohta külmas ja vahelduvas ilmas. Antud töö raames tuvastatakse peamised tegurid, mis põhjustavad külmades oludes elektriauto suurenenud energiatarbimist. Uuringu käigus viidi läbi rida kontrollitud sõiduteste, mille käigus sõideti elektriautoga (Nissan Leaf) korduvalt sama marsruuti erinevates ilmastikutingimustes. Sõidutestide ajal mõõdetud temperatuurid jäid vahemikku +20 °C kuni −15 °C. Kuna 2024/2025. aasta talv oli Balti piirkonnas ebatavaliselt soe, ei olnud võimalik läbi viia katseid madalamatel temperatuuridel. Salvestati ja analüüsiti muutujaid nagu läbitud vahemaa, välistemperatuur, aku laetuse tase ning lisaseadmete kasutus. Lisaks mõõdeti elektriauto kiiruse ja võimsustarbimise vahelist seost ning hinnati energiakadusid aku laadimise ajal. Kogutud andmeid analüüsiti statistiliselt ning töötati välja matemaatilised mudelid, mis võimaldavad täpsemalt prognoosida aku kasutust erinevate välistemperatuuride korral. Tulemused näitavad, et madalad temperatuurid suurendavad oluliselt elektriautode energiatarvet. Peamiselt suureneb energiatarve, kuna aku töötab külmas vähem tõhusalt ning vajalik on täiendav energia salongi kütmiseks. Põhjalikum analüüs näitab, et energiatarbimise suurim tõus toimub temperatuuride vahemikus 0°C kuni −10°C. Uuringu tulemused kinnitavad, et klimaatilised tingimused avaldavad elektrisõidukite sõiduulatusele ja energiatõhususele olulist negatiivset mõju, kusjuures kõige määravamad tegurid on madal välistemperatuur ning sellest tulenev suurenenud energiavajadus salongi kütmiseks. Reaalsetel sõidukatsetel põhinev uurimus annab panuse elektriautode energiatõhususe mõistmiseks Balti piirkonnas ning pakub praktilist teavet nii elektriautode kasutajatele kui ka nende arendajatele.Electric vehicles (EVs) have seen increased interest in recent years as a lower-emission alternative to internal combustion engine (ICE) vehicles, with much of their growth driven by government subsidies and incentives across Europe. However, as these incentives have slowed, the EV market faces new challenges, particularly in the Baltic countries where the climate significantly impacts EV performance. Low temperatures, common in Baltic weather, can notably affect EVs’ range and energy efficiency, influencing operational costs and user satisfaction. Understanding how Baltic weather conditions, primarily temperature, influence the energy consumption of EVs is essential to gaining a deeper understanding of their efficiency in low temperatures and harsh weather conditions. The main aim of this study is to assess the impact of varying weather conditions on EV energy consumption, providing valuable insights into their efficiency under cold and variable climatic conditions. The primary goal is to identify the factors most responsible for increased energy consumption in these conditions. In this study, a series of controlled real-world driving tests were conducted, during which an EV (Nissan Leaf) was driven multiple times along identical routes under different weather conditions. The temperatures during these tests ranged from 20°C to -15°C. The 2024/2025 winter season was unusually warm in the Baltic region; therefore, tests could not be conducted at lower temperatures. Variables such as distance, temperature, battery state, and the use of accessories were recorded and subsequently analysed. Additionally, energy losses during EV battery charging were measured and evaluated. The collected data was analysed statistically, and mathematical models were developed to provide accurate predictions of battery usage under varying ambient temperatures. The results indicate that low temperatures increase EV energy consumption due to the additional energy required for battery and cabin heating. A more detailed analysis reveals that the most significant increase in energy consumption occurs at an ambient temperature of -10°C. Overall, this study demonstrates that Baltic weather conditions can lead to a substantial decrease in EV range and efficiency, with low temperatures being the most impactful factor. By providing real-world data, this study contributes to a deeper understanding of EV efficiency in the Baltic region, offering practical insights for EV users and researchers
Vasepõhiste nanoosakeste optiliste neeldumisomaduste uurimine roheliste fotokatalüütiliste ja fotogalvaaniliste rakenduste jaoks UV-Vis-spektroskoopia abil
No full textBachelor’s thesis
Engineering CurriculumGreen or sunlight-driven photocatalysis and photovoltaics are environmental-friendly
methods for the productions of fuels and electricity, respectively. The aim of this thesis is
to use UV-Vis spectroscopy to analyze the optical properties of copper (Cu)-based
nanoparticles in order to study their capability of absorbing light in the visible part of the
solar spectrum and evaluate them as candidates for green energy production. Cu-based
nanoparticles have good optical, electronic and catalytic properties and small band gaps
of 1.4-2.5 eV for Cu2O and 0.8-1.9 eV for Cu3N, making them potentially effective
materials for the production of energy. Herein, the absorption properties, band gaps and
photocatalytic characteristics of four samples synthesized with different stirring time (20
min, 2 h, 3h and 5 h) using a non-aqueous sol-gel method, were investigated using UVVis spectroscopy. Results were plotted and analyzed using the OriginPro software. The
result suggests that all the samples are sensitive to solar radiation. However, the best
material for green energy production is the one containing the highest quantities of Cu3N
with an absorption range extending up to the near infrared region.Päikesevalgusest juhitud fotokatalüüs ja fotogalvaanika on keskkonnasõbralikud
meetodid kütuste ja elektri tootmiseks. Käesoleva lõputöö eesmärgiks on analüüsida
vasepõhiste nanoosakeste optilisi omadusi, et uurida nende võimet neelata valgust
päikesespektri nähtavas osas ning hinnata neid rohelise energia allika kandidaatidena.
Vasepõhistel nanoosakestel on head optilised, elektroonilised ja katalüütilised omadused
ning kitsas keelutsoon, mis jääb Cu2O puhul vahemikku 1.4-2.5 eV ja Cu3N puhul
vahemikku 0.8-1.9 eV, mistõttu on need potentsiaalselt tõhusad materjalid energia
tootmiseks. Mittevesilahusel põhineval sool-geel meetodil sünteesiti nelja erineva
segamisajaga (20 m, 2 h, 3 h ja 5 h) vasepõhiste nanoosakeste proove. Saadud proove
uuriti seejärel kasutades UV-Vis spektromeetrit. Tulemused kanti graafikule ning
analüüsiti kasutades tarkvara OriginPro. Tulemustest saab järeldada, et kõik proovid
neelavad valgust silmale nähtavas spektri ulatuses. Siiski, parim materjal rohelise energia
tootmiseks sisaldab suures koguses Cu3N nanoosakesi ning neelab valgust ka spektri
lähiinfrapuna piirkonnas
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
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counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
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koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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