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1

Assessment of the product carbon footprint of office equipment across the entire life cycle

Wojciechowski Hubert, Domański Roman

Economics and Environment

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2024

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No. 2

art. no. 757

EN

Purpose: The aim of the article is to publicise the issue of carbon footprint emission from office equipment because this problem is not yet widely recognised in the ICT industry. Methodology/approach: The product carbon footprint (PCF) of various information and communication technologies (ICT) was assessed - 196 products of 12 groups representing a broad spectrum of office equipment - covering the entire life cycle (LCA) from production to disposal. Findings: The level of carbon footprint of a given office device depends on its size, including its energy demand. It should be noted that although smaller devices individually have a smaller carbon footprint, due to their common use (many pieces), they may generate emissions similar to larger ones. Originality/value: The results of the carbon footprint statistics of ICT devices included in the result section may constitute valuable input for companies to calculate the carbon footprint in offices. They can also be used as a data set for the carbon footprint calculator of ICT devices.

PL

Cel: Celem artykułu jest nagłośnienie zagadnienia emisji śladu węglowego ze sprzętu biurowego, gdyż problem ten nie jest jeszcze powszechnie rozpoznany w branży ICT. Metodologia/podejście: Oceniono ślad węglowy produktu (PCF) różnych urządzeń informacyjno-komunikacyjnych (ICT) – 196 produktów z 12 grup reprezentujących szerokie spektrum sprzętu biurowego – obejmujący cały cykl życia (LCA) od produkcji do utylizacji. Wyniki: Poziom śladu węglowego danego urządzenia biurowego zależy od jego wielkości, w tym od zapotrzebowania na energię. Należy zaznaczyć, że choć mniejsze urządzenia indywidualnie mają mniejszy ślad węglowy, to ze względu na ich powszechne użytkowanie (wiele sztuk) mogą generować emisję podobną do większych. Oryginalność/wartość: Wyniki statystyk śladu węglowego urządzeń ICT zawarte w sekcji wyników mogą stanowić cenny wkład dla firm do obliczenia śladu węglowego w biurach. Można je również wykorzystać jako zbiór danych, do kalkulatora śladu węglowego urządzeń ICT.

2

Review of heat management systems for high voltage accumulator in electric vehicles and its perspectives

Dolecki Krzysztof, Kapuściński Jakub, Domański Roman

Rynek Energii

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2022

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Nr 4

36--45

EN

Thermal management of high voltage accumulators used for electric mobility is a complex topic, due to many limiting factors like size, weight, cost of development and implementation, and safety. Advancements in technology created cheaper cells, that can store more energy and have higher power density, which enabled manufacturers to build many new electric vehicles. However, accumulator in EVs is still the most expensive part of electric powertrain and cells are very sensitive to operating conditions. Temperatures outside of their specific range can cause quicker loss of their capacity, lower power performance or even cause thermal runaway events that are almost inextinguishable - that’s why proper thermal management receives a lot of attention. This paper discloses important aspects of accumulators, that have to be considered during thermal design, reviews every current solution, their advantages and disadvantages, with examples of EVs that use them. Current trends and possible changes in near future are then disclosed, to create good knowledge base about current situation and trends on the market to make early phase of conceptual work easier.

PL

Zarządzanie termiczne akumulatorami wysokiego napięcia stosowanymi w pojazdach elektrycznych jest złożonym zagadnieniem ze względu na wiele czynników ograniczających, takich jak rozmiar, waga, koszty opracowania i wdrożenia oraz bezpieczeństwo. Postęp technologiczny pozwolił na stworzenie tańszych ogniw, które mogą przechowywać więcej energii i mają większą gęstość mocy, co umożliwiło producentom wyprodukowanie wielu nowych pojazdów elektrycznych. Mimo to akumulatory w pojazdach elektrycznych nadal stanowią najdroższą część elektrycznego układu napędowego, a ogniwa są bardzo wrażliwe na warunki eksploatacji. Temperatury wykraczające poza właściwy dla nich zakres mogą powodować szybszą utratę pojemności, obniżenie wydajności energetycznej, a nawet wywoływać zjawiska ucieczki cieplnej, które są prawie niemożliwe do ugaszenia - dlatego odpowiednie zarządzanie termiczne jest przedmiotem szczególnego zainteresowania. W tym artykule przedstawiono ważne aspekty akumulatorów, które należy wziąć pod uwagę podczas projektowania termicznego, dokonano przeglądu wszystkich obecnie stosowanych rozwiązań, ich zalet i wad, wraz z przykładami pojazdów elektrycznych, które je wykorzystują. Następnie przedstawiono aktualne trendy i możliwe zmiany w najbliższej przyszłości, aby stworzyć dobrą bazę wiedzy na temat obecnej sytuacji i trendów na rynku, co ułatwi wczesną fazę prac koncepcyjnych.

3

The use of drones in mountain search and rescue (GOPR) in Poland - possibilities and limitations

Domański Roman

LogForum

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2022

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Vol. 18, no. 3

275--284

EN

Background: Distribution using drones is treated as a developmental and promising form of transport in the future - an innovative way of moving about. The literature review showed a lack of a comprehensive and holistic assessment of the phenomenon of the use of drones in mountain search and rescue in Poland, a research gap. The aim of the article is to perform a quantitative and qualitative assessment of this issue, acquiring new knowledge about the basics of phenomena and observable facts (cognitive aspect). Methods: The subject of the study are drones. The scope of the study covers only the mountain search and rescue in Poland. The entities under study are central branches of Mountain Volunteer Search and Rescue (GOPR). The study used the method of an in-depth direct interview carried out with mountain rescuers - drone pilots in GOPR. Results: The result of the analysis of the material from interviews is an assessment of the use of drones in search and rescue in Polish mountains: what drones are already used, in which mountain groups, how many are, how often they are used, what rescue tasks they perform, how many drone pilots there are, what competences they have, what opportunities and problems are associated with the operation of drones in mountainous terrain. Conclusions: Drones are already used in mountain search and rescue by GOPR – mainly for searching for people and monitoring avalanches. At the moment, the scale of the phenomenon is not very impressive. However, drones are treated as a developmental issue in GOPR. In addition to plans to increase the number of drones, GOPR is also considering the introduction of drones into other categories of rescue tasks as well as providing the current fleet with new additional equipment. The main barriers to further proliferation of drones in GOPR are legal, insurance, financial, and behavioral issues.

4

Ocena stanu izolacji na podstawie rozkładu prądu i rezystancji w funkcji czasu trwania pomiaru

Domański Roman

Elektro Info

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2022

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nr 11

59--61

PL

Pomiar rezystancji izolacji polega na zmierzeniu prądu płynącego przez materiał izolacyjny przy napięciu probierczym odpowiednim dla danego obiektu. Wykorzystując prawo Ohma, obliczona zostanie rezystancja izolacji materiału, z którego ta izolacja została wykonana. Parametr ten – dzięki możliwości porównania go do wartości wymaganych – uważany jest powszechnie za ostatecznie wystarczający do dokonania oceny, czy stan izolacji obiektu jest zadowalający, czy nie.

5

How to measure omnichannel? Marketing indicator-based approach - theory fundamentals

Domański Roman

LogForum

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2021

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Vol. 17, no. 3

373--385

EN

Background: The ability to assess a situation is one of the key competences of companies operating on the market. One should know if one functions as well as their competitors, better or perhaps worse. In the case of the omnichannel concept, it is difficult to answer this question, since so far there has been no recognized standard for its evaluation. The aim of the article is to present the theory fundamentals of omnichannel measurement and evaluation in an indicator-based form. Methods: The theoretical part features a systematic literature review based on the Scopus abstract and citation database. In the research part, an original indicator-based omnichannel measurement and evaluation theory was presented. The idea was based on the following ideas: marketing mix, benchmarking, OTIFEF, AHP. Results: In the scientific literature, the dominant evaluation of omnichannel is based on financial measures, which, according to the author of this article, does not reflect the essence of the functioning of this concept. Therefore, the research part presents relational omnichannel indicators - individual (4) and aggregate (11) - based on non-financial measures. Conclusions: There are currently no reference omnichannel evaluation instruments. The creation and functioning of such a standard would allow to form objective opinions. The standardization of the omnichannel measurement would enable to perform comparative analyses, the results of which could be used to further improve trade and distribution processes in companies using this sales strategy. The research approach adopted in the article fits very well with the assumptions of the omnichannel concept. The proposed measurement and evaluation theory is simple and universal, and its application is not constrained by any limitations. It enables both individual and comparative evaluation.

6

Method for efficient feasibility study of air cooling systems for modern PMSM electric motors in all-electric aviation

Kapuściński Jakub, Domański Roman

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 1

89--96

EN

In this paper, the authors present a computational model of a fin-based air cooling system for Permanent Magnet Synchronous Machine (PMSM) electric motors. The model can be used as a method for fast and efficient feasibility studies of air cooling for PMSM motors in hybrid-electric or all-electric aviation applications, supplementing further research (thermal resistance networks, and FEA/CFD-CHT models). In the paper, authors provide temperature distributions along the fin height which are calculated and presented for a straight fin, followed by heat transfer rate from fin surface and fin efficiency. A parameter to compare different fin materials for aviation applications is introduced – heat transfer rate from the fin to fin mass ratio. Aluminum and copper fins are compared. Different shapes of straight fin are considered and compared. The above parameters and comparison are then calculated and given for circular fins. Parameters of the whole fin-based air cooling system for specific 140 kW PMSM motor are calculated and presented.

7

Pomiar rezystancji uziemień rozległych metodą nachylenia zbocza

Domański Roman

Elektro Info

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2020

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nr 9

89--91

PL

W artykule przedstawiona zostanie metoda nachylenia zbocza. Stanowi ona punkt wyjścia do wyprowadzenia powyższego wzoru. Umożliwia badania rozległych uziemień i ocenę poprawności otrzymanych wyników. Różnica polega na przeprowadzeniu trzech pomiarów w celu ustalenia pozycji elektrody napięciowej i fizycznego przeprowadzenia właściwego pomiaru, a nie tylko ograniczania się do wyliczenia jej wartości ze wzoru.

8

Investigation of thermal properties of novel phase change material mixtures (octadecane-diamond) with laser flash analysis

Sierakowski Mateusz, Godlewski Wojciech, Domański Roman, Kapuściński Jakub, Wiśniewski Tomasz, Kubiś Michał

Journal of KONES

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2019

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Vol. 26, No. 4

211--218

EN

Phase change materials (PCMs) are widely used in numerous engineering fields because of their good heat storage properties and high latent heat of fusion. However, a big group of them has low thermal conductivity and diffusivity, which poses a problem when it comes to effective and relatively fast heat transfer and accumulation. Therefore, their use is limited to systems that do not need to be heated or cooled rapidly. That is why they are used as thermal energy storage systems in both large scale in power plants and smaller scale in residential facilities. Although, if PCMs are meant to play an important role in electronics cooling, heat dissipation, or temperature stabilization in places where the access to cooling water is limited, such as electric automotive industry or hybrid aviation, a number of modifications and improvements needs to be introduced. Investigation whether additional materials of better thermal properties will affect the thermal properties of PCM is therefore of a big interest. An example of such material is diamond powder, which is a popular additive used in abradants. Its thermal diffusivity and conductivity is significantly higher than for a pure PCM. The article presents the results of an analysis of the effect of diamond powder on thermal conductivity and diffusivity of phase change materials in the case of octadecane.

9

Investigation of the effect of diamond powder on the thermal properties of octadecane using differential scanning calorimetry

Godlewski Wojciech, Sierakowski Mateusz, Domański Roman, Kapuściński Jakub

Journal of KONES

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2019

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Vol. 26, No. 3

39--45

EN

The purpose of this work was to examine the effect of diamond powder on the thermal properties of phase change materials on the example of octadecane. The experiment involved mixing of diamond powder with a specific granulation with the aforementioned representative of the alkanes group. Two different grain sizes were used: 50 and 250 micrometres. The change of specific heat, latent heat of phase change and degree of supercoiling in newly formed mixtures was compared to the pure forms of the phase-change materials used. Initial mixing with a glass-stirring rod showed strong stratification for each granulation due to the low viscosity of the mixture and too large differences between component densities. It was decided to add amorphous silicon dioxide to the mixtures, which increases density of the mixture. The optimal percentage of amorphous silicon dioxide was estimated experimentally. Measurements of thermal parameters were carried out using DSC technology. The results of the tests of specific heat and latent phase transition heat showed that with the increasing content of diamond, the specific heat of the mixture decreases almost twice, and the latent heat can decrease by up to three times. The effect of diamond powder on reducing the degree of supercoiling of the mixture was also observed. An important observation was that the mixture with higher granulation of diamond powder had greater tendency for sedimentation. This method could be used to increase thermal conductivity and diffusivity of phase change materials and make them viable for use in systems that require cooling at high rate or temperature stabilization, such as control systems in electronic vehicles or aviation industry and at the same time decrease the degree of supercoiling which could increase the efficiency of system.

10

Ochrona przed porażeniem prądem elektrycznym poprzez samoczynne wyłączenie zasilania

Domański Roman

Elektroinstalator

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2019

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nr 6

17--22

PL

Eksploatacja instalacji elektrycznych jest tak powszechna, że zdecydowana większość ludzi nie zdaje sobie sprawy z zagrożeń, jakie może napotkać, jeżeli w użytkowanym urządzeniu nagle wystąpi uszkodzenie, np. zwarcie. W celu zapobieżenia niebezpieczeństwu porażenia prądem elektrycznym instalacje muszą być tak skonstruowane, aby zminimalizować tego rodzaju zagrożenia.

11

Metoda techniczna pomiaru rezystancji uziemienia

Domański Roman, Osiecki Jacek

Elektro Info

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2019

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nr 11

19--21

PL

Do właściwego wykonania pomiarów rezystancji uziemienia, różnych obiektów, nie wystarczy dobry przyrząd pomiarowy. Konieczna jest przede wszystkim znajomość właściwości metody technicznej, aby poprawnie zbudować układ pomiarowy. W artykule opisano cechy metody technicznej (spadku potencjału) oraz zmiany w podejściu do badań w zależności od rozległości badanego uziemienia.

EN

For proper measurements of earth resistance, various objects, a good measuring device is not enough. First of all, it is necessary to know the properties of the technical method to properly build the measuring system. The article describes the features of the technical method (fall of potential) and changes in the approach to test depending on the extent of the grounding tested.

12

Relation between thermal conductivity and coordination number for fibre-reinforced composite with random distribution of fibres

Darnowski Piotr, Furmański Piotr, Domański Roman

Archives of Thermodynamics

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2019

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Vol. 40, no 1

21--48

EN

Transverse effective thermal conductivity of the random unidirectional fibre-reinforced composite was studied. The geometry was circular with random patterns formed using random sequential addition method. Composite geometries for different volume fraction and fibre radii were generated and their effective thermal conductivities (ETC) were calculated. Influence of fibre-matrix conductivity ratio on composite ETC was investigated for high and low values. Patterns were described by a set of coordination numbers (CN) and correlations between ETC and CN were constructed. The correlations were compared with available formulae presented in literature. Additionally, symmetry of the conductivity tensor for the studied geometries of fibres was analysed.

13

Investigation of non-Fourier thermal waves interaction in a solid material

Lenarczyk Marcin, Domański Roman

Archives of Thermodynamics

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2019

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Vol. 40, no 1

115--126

EN

In this paper, effects of non-Fourier thermal wave interactions in a thin film have been investigated. The non-Fourier, hyperbolic heat conduction equation is solved, using finite difference method with an implicit scheme. Calculations have been carried out for three geometrical configurations with various film thicknesses. The boundary condition of a symmetrical temperature step-change on both sides has been used. Time history for the temperature distribution for each investigated case is presented. Processes of thermal wave propagation, temperature peak build-up and reverse wave front creation have been described. It has been shown that (i) significant temperature overshoot can appear in the film subjected to symmetric thermal load (which can be potentially dangerous for reallife application), and (ii) effect of temperature amplification decreases with increased film thickness.