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  • The impact of global value chains on wages, employment, and productivity: a survey of theoretical approaches
    • Sabina Szymczak
    2024 Pełny tekst Journal for Labour Market Research

    This study presents a systematic literature review to provide a collection of theories explaining the impact of global value chains (GVCs) on labour market outcomes. Due to the complex nature of GVCs and the interconnectedness of wages, employment, and productivity, many direct and indirect effects are at play. To ensure a transparent and systematic flow of the review process, I follow the PRISMA guide. Eventually, 36 records out of 1221 results from Scopus database were selected. This review may be useful for theorists, empirical economists, and policy makers as an overview of theoretical developments and convenient map of potential outcomes expected from involvement in GVCs. It identifies and systematizes a number of effects existing in the literature under various names. The results show that the predictions from the theory are ambiguous. The positive effects which may emerge regardless the characteristics of the GVC are the productivity-enhancing effect and the cross-effect, especially important considering growing servicification of manufacturing. Here lies the critical role of the state and policies to assure that the losses will not exceed the gains in the aggregate terms. One of the main factors shaping the outcome is the power distribution among the GVC’s firms. Additionally, this paper shows the shortcomings of the existing theories. Less aggregated levels of analysis could be a great input to the discussion, as well as addressing different GVCs’ dimensions and types of organisation. The understanding of relation between GVC position and labour market is especially worth exploration as the existing evidence adopt different and even contradicting perspectives on the definition of upgrading the GVC position.

  • The impact of graphene on the electrochemical performance of BiMeVOx catalysts in water splitting
    • Patrycja Grabowska
    • Mariusz Szkoda
    • Malgorzata Skorupska
    • Marta Gajewska
    • Anna Ilnicka
    2024 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    The development of efficient catalysts for electrochemical water splitting has become a significant contemporary challenge. Transition metal oxides, due to their unique electrochemical properties, have emerged as promising candidates. Among these, a group of BiMeVOx-based compounds shows particular potential for practical applications in hydrogen and oxygen evolution reactions. However, improvement is still necessary to achieve stable operation of these catalysts in green hydrogen generation. With this is mind, in this study we synthesize BiMeVOx materials with graphene addition using a simple annealing in a tube furnace and investigate their electrochemical properties in HER and OER. After incorporating different metals into the BiMeVOx structure, we observed variations in electrochemical properties; materials with the addition of molybdenum and cobalt (BiMoVOx and BiCoVOx) outperformed materials containing zirconium and cerium (BiZrVOx and BiCeVOx). The BiMoVOx/C catalyst showed excellent HER performance with an overpotential of 432 mV at 10 mA/cm2 and a Tafel slope of 76 mV dec⁻1, while BiCoVOx/C exhibited superior OER activity with a Tafel slope of 100 mV dec⁻1, lower than that of commercial IrO₂. The addition of graphene improved the conductivity and overall activity of the catalysts. These findings indicate that metal doping and graphene incorporation are effective strategies for enhancing the performance of BiMeVOx-based materials in water splitting applications.

  • The Impact of Hybrid Flame Retardant Compositions on the Performance of Foamed Flexible Polyurethane/Ground Tire Rubber Composites
    • Paulina Kosmela
    • Adam Olszewski
    • Mateusz Barczewski
    • Adam Piasecki
    • Aleksander Hejna
    2024 JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE

    Current sustainability-oriented trends affect polyurethane (PU) materials and stimulate the incorporation of recycled or waste-based materials as fillers. Ground tire rubber (GTR) poses as an auspicious candidate due to the excellent performance of car tires. Despite the benefits related to the mechanical performance, it contributes to the increasing flammability of the resulting composites. Herein, presented work assessed the impact of hybrid flame retardant (FR) combinations of ammonium polyphosphate (APP) or melamine cyanurate (MC) with organophosphorus compounds on the performance of foamed flexible PU/GTR composites. Such works are of vital importance, because matching to the needs of material with the mode of action of particular FRs is quite challenging. Except for the flammability reduction, they also affect structure and performance of composites. Fire resistance was enhanced for all applied FRs compositions; however, APP was found more effective than MC due to the efficient formation of protective char layer. Moreover, introduction of MC induced heterogeneity of cellular structure and excessive stiffening of PU structure, which increased its friability and cells’ coalescence, deteriorating thermal insulation performance and damping ability.

  • The influence of azide and imidazole on the properties of Mn- and Cd-based networks: conductivity and nonlinear phenomena
    • Monika Trzebiatowska
    • Dorota A. Kowalska
    • Agnieszka Ciżman
    • Natalia Wójcik
    • Ryszard Barczyński
    • Adam Pikul
    • Jan K. Zaręba
    • Marcin Palewicz
    • Tomasz Piasecki
    • Krystian Roleder
    • Marek Gusowski
    • Mirosław Mączka
    2024 Journal of Materials Chemistry C

    We report a study on a family of four new Mn- and Cd-azide-imidazolate-based compounds with various crystal architectures. Notably, three of these compounds display noncentrosymmetric crystal arrangements at room temperature, a rare phenomenon in hybrid organic–inorganic materials. Both nonlinear optical (NLO) and electrical phenomena in these compounds are observed. The NLO processes include second and third harmonic generation, while the electrical nonlinear phenomena include the presence of polarization and a coercive field in the capacitance measurements (1–2 μC cm−2), and a piezoelectricity with ca. d33 = 0.2 × 10−12 m V−1 coefficient. Additionally, the presence of the second and third harmonics is detected in DC conductivity measurements. The phase transition (PT) present in Mn-based compounds at ca. 370 K is confirmed by DSC, X-ray diffraction, Raman spectroscopy, dielectric, DC conductivity and capacitance measurements. The PT is triggered by the motions of imidazole molecules around a nitrogen-metal bond with minor adjustment of azide bridges in response to this motion as derived from the X-ray diffraction and spectroscopic data. Mn-analogues also feature antiferromagnetic order. Both Cd- and Mn-imidazolate-azides exhibit a conductivity, with a mixed electron/proton hopping transport mechanism, in the case of Cd- similar to those of classic semiconductors.

  • The influence of bio-based monomers on the structure and thermal properties of polyurethanes
    • Janusz Datta
    • Joanna Brzoska
    • Hynek Benes
    • Václav Pokorný
    • Rafał Konefał
    2024 Scientific Reports

    Most polyurethanes (PU) are currently produced through the polyaddition reaction of polyisocyanates with polyols and chain extenders, using components of petrochemical origin. From an environmental and geopolitical point of view, and with regard to the problems of oil supply and processing, the replacement of petrochemical PU raw materials with renewable resources is highly desirable. It is also one of the principles of sustainable development and an important challenge for chemical companies and market competitiveness. Current research studies focus mainly on the use of bio-based polyols for PUs, while other PU components, in particular polyisocyanates, remain of petrochemical origin. In this work, a series of PUs have been synthesized by polyaddition reactions of different types of renewable polyols and bio-based polyisocyanates. The effects of the bio-derived components on the structure, thermal stability and phase transformations of the PU were studied using FTIR and NMR spectroscopy, SWAXS, TGA, DSC, DMTA and TGA-FTIR. A full conversion of the bio-based monomers was achieved in all cases, indicating good compatibility and reactivity of all bio-based components. It was observed that bio-based PU exhibited a lower degree of phase separation and slightly lower thermal stability compared to PUs from petrochemical monomers.

  • The influence of brace to chord rotational connection stiffness on stability of the truss
    • Marcin Krajewski
    2024 Bulletin of the Polish Academy of Sciences-Technical Sciences

    The paper is devoted to the numerical analysis of the roof truss subjected to upward wind loading and braced at the tensioned top chord. The linear buckling analysis were performed for the beam and shell model of the structure. As the result the influence of rotational connection stiffness between the brace and the top chord on the truss stability was appointed. The biaxial strength testing machine was used to conduct the experimental tests of the rotational connection stiffness between selected steel profiles. The results in the form of measured structural displacements and rotations were presented. The static nonlinear analysis results performed for the shell model of the structural connection were compared to the results obtained on the experimental set-up.

  • The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans
    • Anna Sadowska-Rociek
    • Joanna Doniec
    • Barbara Kusznierewicz
    • Tomasz Dera
    • Agnieszka Filipiak-Florkiewicz
    • Adam Florkiewicz
    2024 Foods

    Cruciferous vegetables represent a valuable source of bioactive compounds. However, there is currently a deficiency of information regarding the extent to which these compounds remain bioaccessible to the body following thermal treatment and digestion processes within the digestive tract. Accordingly, the aim of this study was to evaluate the impact of heat treatment and in vitro digestion on the level of selected bioactive compounds in Brussels sprouts. The Brussels sprouts samples were subjected to a range of thermal processing techniques, which were then followed by a simulated in vitro digestion. The investigated compounds were analyzed using UV-Vis spectrometry and liquid chromatography coupled with mass spectrometry (LC-MS). The findings revealed that the sous-vide method of cooking Brussels sprouts resulted in significantly higher losses of glucosinolates (GLS) in comparison to conventional cooking methods. No significant differences were observed with regard to isothiocyanates and indoles. The analysis of GLS following digestion revealed that the process was more effective after sous vide and traditional cooking, and slightly less effective after steam cooking. With regard to individual compounds, glucoraphanin (GRA), glucoraphenin (GIV), and gluconasturtiin (GNS) were found to be completely degraded, whereas methoxyglucobrassicin (metGBS) was the most resistant to digestion in both the sous vide and steamed Brussels sprouts. The results indicated that the process of simulating digestion had no significant impact on isothiocyanates and indoles. This suggests that, if present in the heat-treated samples, these compounds remained stable during the in vitro digestion procedure.

  • The Influence of Global Corrosion Degradation on Localized Damage Detection Using Guided Waves
    • Beata Zima
    • Emil Roch
    • Jochen Moll
    2024

    This paper presents the results of a numerical analysis of the influence of corrosion degradation of metal plates on the wave propagation phenomenon. There are several different corrosion types, but general and pitting corrosion are the most common. General corrosion is more or less uniformly distributed over the entire exposed surface of the metal while pitting corrosion takes the form of localized cracks. Because the general corrosion is related to thickness reduction and in consequence, wave propagation velocity, this study is focused on the influence of the variable thickness of corroded plate described by the statistical descriptors (average thickness, standard deviation and coefficient of variation) on the uncertainty of localized damage detection based on the algorithms incorporating velocity of the guided wave. Numerical simulations were conducted for corroded plates with localized cut-through damage. The irregular surface of the plates was modeled using random fields. In this study, the plates varying in degree of degradation (DoD) as well as in geometry of the surface have been analyzed. Such an approach allowed for observing the effects of both thickness reduction and the exact geometry of corroded plates on damage detection and localization. The common approach based on delay and sum algorithm to detect and localize damage has been applied here.

  • The Influence of Impact Velocity on Stresses and Failure of S355j2 Steel Under Slurry Erosion Conditions
    • Dominika Zakrzewska
    • Marta H. Buszko
    2024 Pełny tekst Advances in Science and Technology Research Journal

    The purpose of this work was to determine the essence of the influence of the impact velocity (5, 7, and 9 m/s) on Hertzian stresses and the erosion mechanism of ferritic-pearlitic S355J2 steel. The investigations were carried out using a slurry pot tester. S355J2 steel showed a strong sensitivity to changes in impact velocity. A significant increase in erosion rate was observed at a velocity of 9 m/s. This increase was 5-fold and over 15-fold compared to velocities of 7 m/s and 5 m/s, respectively. The study of Hertzian stress is crucial in erosion research because it helps understand how impact energy is absorbed by the eroded material and the mechanisms that cause surfacewear. A linear increase in mean contact pressure and maximum shear stress was observed with increasing impactvelocity. The mean contact pressure increased from 4.3 GPa to 5.5 GPa and the maximum shear stress increasedfrom 2.0 GPa to 2.5 GPa. The kinetic energy of the solid particles that hits the eroded steel is distributed in the con-tact area, which leads to various deformations and wear mechanisms. The primary type of deformation was fatiguedegradation of the surface layers of the eroded steel. The high kinetic energy of solid particles contributed to theformation of plastic deformations and strongly deformed steel flakes. Higher impact velocities generally result ingreater forces and contact stresses on the material surface. This led to the intensification of plastic deformation inthe contact areas and increased the Hertzian stresses.

  • The influence of the geographic positioning system error on the quality of ship magnetic signature reproduction based on measurements in sea conditions
    • Jarosław Tarnawski
    • Krystian Buszman
    • Mirosław Wołoszyn
    • Bartosz Puchalski
    2024 Pełny tekst MEASUREMENT

    In previous studies, the authors performed the magnetic signature reconstruction of the marine ship Zodiak as part of the measurement campaign focused on recording magnetic data and the relative position of a ship during its passage over a magnetometer immersed on the testing ground. A high degree of representation of the magnetic signature was obtained. However, the recorded measurement data revealed new patterns of the multidipole model behavior that were not observed in the synthetic data based analyzes. It was assumed that the main factor influencing the abovementioned behavior of the model is the error in determining the geographical position of the ship in relation to the magnetometer. Therefore, another research was carried out to determine the relative position of the ship and the measurement device in sea conditions, in the area of the test site used in the previous study. For this purpose, two different classes of GPS receivers were used. The first receiver was the same as that used to determine the position of Zodiak in the previous measurement campaign, while the second receiver, treated as a reference, was a top-class geodetic receiver. The difference in indications between these two receivers gave a picture of the scale of errors in the data recorded during the previous measurement campaign. These errors are used in the article to analyze the effect of inaccuracies in determining the ship position on the quality of magnetic signature reproduction. Two types of signature reproduction error were introduced – the error based only on the data collected from the ship’s paths, and the error in the entire area of magnetic anomaly. The model of Zodiak was used to determine the value of the magnetic flux outside the paths. Profiles of differences in indications of GPS receivers at sea which were obtained from actual measurements were used to analyze the errors in determining the ship position. A measurable result of the work reported in the article is the map of the loss of quality of magnetic signature reproduction as a function of the ship position determination error, which can indicate the range of applicability of the model and the described method.

  • The influence of α,ω-diols and SiO2 particles on CO2 absorption and NH3 escaping during carbon dioxide capture in ammonia solutions
    • Temesgen Amibo
    • Donata Konopacka-Łyskawa
    2024 Pełny tekst Journal of CO2 Utilization

    Ammonia solutions are widely used solvents for CO2 capture. However, a significant disadvantage of these solvents is secondary pollution of the purified gas stream by desorbed ammonia. In this work, α,ω-diols, and colloidal silica have been proposed to reduce this undesired effect. Ammonia solutions with the addition of ethylene glycol (EG), 1,3-propanediol (PRD), 1,4-butanediol (BUD), 1,5-pentanediol (PED), or 1,6-hexanediol (HED) and ammonia solution with the addition of diol and colloidal SiO2 were tested. The concentration of CO2 and NH3 in the exhaust gas was continuously measured during the experiments. Based on the recorded measurements, the number of moles of CO2 absorbed and the number of moles of NH3 lost were calculated. Mass transfer coefficients for CO2 absorption and NH3 desorption were also determined. The studies showed that CO2 absorption occurred faster in ammonia solutions with EG, PRD, BUD, and HED, and the CO2 loading was higher than in pure NH3 solution. The most effective additive improving CO2 absorption was BUD, followed by HED. SiO2 particles improved slightly the absorption efficiency in most of the tested diol solutions. All diols used inhibited the escape of ammonia, with PED having the most effective effect. However, adding silica particles effectively inhibited ammonia escape in all tested systems.

  • The Input of Nanoclays to the Synergistic Flammability Reduction in Flexible Foamed Polyurethane/Ground Tire Rubber Composites
    • Aleksander Hejna
    • Paulina Kosmela
    • Adam Olszewski
    • Wiktoria Żukowska
    2024 Materials

    Currently, postulated trends and law regulations tend to direct polymer technology toward sustainability and environmentally friendly solutions. These approaches are expressed by keeping materials in a loop aimed at the circular economy and by reducing the environmental burdens related to the production and use of polymers and polymer-based materials. The application of recycled or waste-based materials often deals efficiently with the first issue but at the expense of the final products’ performance, which requires various additives, often synthetic and petroleum-based, with limited sustainability. Therefore, a significant portion of research is often required to address the drawbacks induced by the application of secondary raw materials. Herein, the presented study aimed to investigate the fire performance of polymer composites containing highly flammable matrix polyurethane (PU) foam and filler ground tire rubber (GTR) originating from car tire recycling. Due to the nature of both phases and potential applications in the construction and building or automotive sectors, the flammability of these composites should be reduced. Nevertheless, this issue has hardly been analyzed in literature and dominantly in our previous works. Herein, the presented work provided the next step and investigated the input of nanoclays to the synergistic flammability reduction in flexible, foamed PU/GTR composites. Hybrid compositions of organophosphorus FRs with expandable graphite (EG) in varying proportions and with the addition of surface-modified nanoclays were examined. Changes in the parameters obtained during cone calorimeter tests were determined, discussed, and evaluated with the fire performance index and flame retardancy index, two parameters whose goal is to quantify the overall fire performance of polymer-based materials.

  • The Interplay between Endogenous and Foodborne Pro-Oxidants and Antioxidants in Shaping Redox Homeostasis
    • Patrycja Jakubek
    • Karol Parchem
    • Mariusz R. Wieckowski
    • Agnieszka Bartoszek-Pączkowska
    2024 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Oxidative stress has been known about in biological sciences for several decades; however, the understanding of this concept has evolved greatly since its foundation. Over the past years, reactive oxygen species, once viewed as solely deleterious, have become recognized as intrinsic components of life. In contrast, antioxidants, initially believed to be cure-all remedies, have failed to prove their efficacy in clinical trials. Fortunately, research on the health-promoting properties of antioxidants has been ongoing. Subsequent years showed that the former assumption that all antioxidants acted similarly was greatly oversimplified. Redox-active compounds differ in their chemical structures, electrochemical properties, mechanisms of action, and bioavailability; therefore, their efficacy in protecting against oxidative stress also varies. In this review, we discuss the changing perception of oxidative stress and its sources, emphasizing everyday-life exposures, particularly those of dietary origin. Finally, we posit that a better understanding of the physicochemical properties and biological outcomes of antioxidants is crucial to fully utilize their beneficial impact on health.

  • The KLC Cultures Synergy for Organizational Agility. Trust, Risk-Taking Attitude, and Critical Thinking as Moderators
    • Wioleta Kucharska
    • Maciej Kucharski
    • Tomasz Balcerowski
    2024 Pełny tekst

    Organizational agility is visible in organizational change adaptability, and it is based on the development of dynamic capabilities, strategic sensitivity of leaders, accuracy and timing of decision-making, learning aptitude, flexibility in thinking and acting, and smooth resource flow across organizations, including the knowledge resource. In such a context, this study aimed to expose how the knowledge, learning, and collaboration cultures approach (KLC) supports organizational agility when this relation is moderated by mutual trust among employees, risk-taking attitude, and critical thinking abilities. Based on the sample composed of 640 Polish knowledge workers and data analyzed with the structural equation modeling method (SEM), this study's results proved that the KLC culture synergy supports organizational agility building and that the mistakes acceptance component of learning culture is critical. Moreover, trust among workmates, risk-taking readiness, and critical thinking skills are significant mediators. The key novelty was exposed through the negative influence of a risk-taking attitude (uncertainty acceptance) on agility. Precisely, the lack of risk acceptance or, reversely, the risk-avoidance attitude supports agility. This is because agility, understood as smooth adaptability, is the effect of efficient risk management. Thanks to risk management and critical thinking, the negative impact of inaction risks can often be seen as higher than the risks of very innovative actions. The KLC approach, critical thinking, and trust among workmates support the smooth selection of risks that must be taken in today's dynamic business. Risk is inevitable. So, from this point, the essence of agility is the ability to smoothly and wisely select among risks that should be taken or avoided. In summary, agility can be considered to be the smooth selection of acceptable risks

  • The KLC Cultures' Synergy Power, Trust, and Tacit Knowledge for Organizational Intelligence
    • Wioleta Kucharska
    • Denise A. D. Bedford
    2024 Pełny tekst Electronic Journal of Knowledge Management

    This paper examines the impact of knowledge, learning, and collaboration culturessynergy (the KLC approach) on organizational adaptability. The SEM analysis method was applied to verify the critical assumption of this paper: that the KLC approach and trust support knowledge-sharing processes (tacit and explicit) and are critical for organizational intelligence activation.Specifically, the empirical evidence, based on a 640-case sample composed of Polish knowledge workers, revealedthat knowledge sharing, organizational intelligence, and innovativeness are vital benefits of the KLC cultures’synergy. It also highlighted that trust among workmates is critical to sustaining tacit knowledge sharing in an organization. Tacit knowledge, which is knowledge that is difficult to transfer to another person by means of writing it down or verbalizing it, is clearly identified as a key component of change adaptability, which is viewed as a measure oforganizational intelligence. Moreover, the acceptance of mistakesas a learning source -a learning culturecomponentthat supports trial-error learning,was found to betremendous for knowledge-sharing processes, organizational intelligence (change adaptability),and innovativeness. Thisstudyproved that knowledge sharing, organizational intelligence, and innovativeness are vitalbenefits of the synergy that offers the KLC cultures. Trust strengthens this effect. So, to gain these benefits, knowledge-driven organizations should employ trusted managers who trust others and, in addition to their professional credentials, exhibit strong habits of respecting knowledge, learning, and collaboration.

  • The landscape in the informal education of the youngest
    • Marta Koperska-Kośmicka
    2024 Pełny tekst Journal of Geography, Politics and Society

    The European Landscape Convention, adopted in 2000, aims to promote the protection, management and planning of landscapes and to organise cooperation on landscape-related issues. Countries that ratified the Convention undertook to introduce activities that would promote public education on the subject. In Poland, the Ministry of Education has identified schools as the place to implement these priorities. In the core curriculum of general education for primary schools, «creating opportunities to learn about the components of the landscape» was prescribed as the primary objective of the subject of nature. Although the school should play a leading role in the implementation of these tasks, even in its most elaborate form it is unable to meet all the needs. It should be complemented by non-formal education, which goes beyond the school curriculum and is a kind of its extension. This article is an attempt to present and evaluate the author’s educational project dealing with the topic of cultural landscape at the regional level.

  • THE METHODS OF TEACHING / LEARNING STRUCTURAL MECHANICS
    • Marek Skowronek
    2024 Pełny tekst

    Structural mechanics is a key issue to study for engineers. A high rank and high social responsibility profession requires both a high graded and intuitive approach. The evolution of learning / teaching methodology follows the novel technical achievements of every decade. The aim remains the same: to produce a professional to perform advanced relevant analysis and safe, optimal structural design

  • The pulse width modulation strategy for a five-phase three-level NPC voltage source inverter with DC-link voltage balancing ability
    • Dmytro Kondratenko
    2024 Pełny tekst

    The doctoral dissertation is all about the development of the space vector modulation algorithm for controlling the generation of output voltage vectors in a three-level, five-phase NPC inverter. The developed algorithm can be used to control five-phase motors, where it will be possible to increase the motor torque by 15%; by appropriate injection of 3rd harmonic current. The proposed control approach also opens up the possibility of independent control of two electric motors, supplied from a single inverter. The critical issues that need to be solved when creating pulse-width modulation algorithms for multiphase, three-level inverters are the need to simultaneously balance the input splitting DC-link capacitor voltages and ensure correct generation of many independent voltage vectors. This scenario is also applicable to the case when the DC-link voltages are of different values. The proposed solution paves way for independent syntheses of output voltages with minimum number of active switches’ transitions; while allowing for appropriate voltage distribution on the DC-link capacitors.

  • The relative cup-length in local Morse cohomology
    • Thomas O. Rot
    • Maciej Starostka
    • Nils Waterstraat
    2024 Topological Methods in Nonlinear Analysis

    Local Morse cohomology associates cohomology groups to isolating neighborhoods of gradient flows of Morse functions on (generally non-compact) Riemannian manifolds M. We show that local Morse cohomology is a module over the cohomology of the isolating neighborhood, which allows us to define a cup-length relative to the cohomology of the isolating neighborhood that gives a lower bound on the number of critical points of functions on M that are not necessarily Morse. Finally, we illustrate by an example that this lower bound can indeed be stronger than the lower bound given by the absolute cup-length.

  • THE REPRESENTATION PROBLEM FOR A DIFFUSION EQUATION AND FRACTAL R-L LADDER NETWORKS
    • Jacky Cresson
    • Anna Szafrańska
    2024 Proceedings of the Institute of Mathematics and Mechanics

    The representation problem is to prove that a discretization in space of the Fourier transform of a diffusion equation with a constant diffusion coefficient can be realized explicitly by an infinite fractal R-L ladder networks. We prove a rigidity theorem: a solution to the representation problem exists if and only if the space discretization is a geometric space scale and the fractal ladder networks is a Oustaloup one. In this case, the resistance and inertance of the ladder are explicitly determined up to a constant.