Academic literature on the topic 'Amiet theory'

This paper presents a new formulation for trailing edge noise radiation from rotating blades based on an analytical solution of the convective wave equation. It accounts for distributed loading and the effect of mean flow and spanwise wavenumber. A commonly used theory due to Schlinker and Amiet predicts trailing edge noise radiation from rotating blades. However, different versions of the theory exist; it is not known which version is the correct one, and what the range of validity of the theory is. This paper addresses both questions by deriving Schlinker and Amiet's theory in a simple way and by comparing it with the new formulation, using model blade elements representative of a wind turbine, a cooling fan and an aircraft propeller. The correct form of Schlinker and Amiet's theory is identified. It is valid at high enough frequency, i.e. for a Helmholtz number relative to chord greater than one and a rotational frequency much smaller than the angular frequency of the noise sources.

Direct numerical simulations (DNS) are conducted of turbulent flow passing an infinitely thin trailing edge. The objective is to investigate the turbulent flow field in the vicinity of the trailing edge and the associated broadband noise generation. To generate a turbulent boundary layer a short distance from the inflow boundary, high-amplitude lifted streaks and disturbances that can be associated with coherent outer-layer vortices are introduced at the inflow boundary. A rapid increase in skin friction and a decrease in boundary layer thickness and pressure fluctuations is observed at the trailing edge. It is demonstrated that the behaviour of the hydrodynamic field in the vicinity of the trailing edge can be predicted with reasonable accuracy using triple-deck theory if the eddy viscosity is accounted for. Point spectra of surface pressure difference are shown to vary considerably towards the trailing edge, with a significant reduction of amplitude occurring in the low-frequency range. The acoustic pressure obtained from the DNS is compared with predictions from two- and three-dimensional acoustic analogies and the classical trailing-edge theory of Amiet. For low frequencies, two-dimensional theory succeeds in predicting the acoustic pressure in the far field with reasonable accuracy due to a significant spanwise coherence of the surface pressure difference and predominantly two-dimensional sound radiation. For higher frequencies, however, the full three-dimensional theory is required for an accurate prediction of the acoustic far field. DNS data are used to test some of the key assumptions invoked by Amiet for the derivation of the classical trailing-edge theory. Even though most of the approximations are shown to be reasonable, they collectively lead to a deviation from the DNS results, in particular for higher frequencies. Moreover, because the three-dimensional acoustic analogy does not provide significantly improved results, it is suggested that some of the discrepancies can be attributed to the approach of evaluating the far-field sound using a Kirchhoff-type integration of the surface pressure difference.

The study of clay tokens in the Ancient Near East has focused, for the most part, on their role as antecedents to the cuneiform script. Starting with Pierre Amiet and Maurice Lambert in the 1960s the theory was put forward that tokens, or calculi, represent an early cognitive attempt at recording. This theory was taken up by Denise Schmandt-Besserat who studied a large diachronic corpus of Near Eastern tokens. Since then little has been written except in response to Schmandt-Besserat's writings. Most discussions of tokens have generally focused on the time period between the eighth and fourth millennium bc with the assumption that token use drops off as writing gains ground in administrative contexts. Now excavations in southeastern Turkey at the site of Ziyaret Tepe — the Neo-Assyrian provincial capital Tušhan — have uncovered a corpus of tokens dating to the first millennium bc. This is a significant new contribution to the documented material. These tokens are found in association with a range of other artefacts of administrative culture — tablets, dockets, sealings and weights — in a manner which indicates that they had cognitive value concurrent with the cuneiform writing system and suggests that tokens were an important tool in Neo-Assyrian imperial administration.

The shear layer characteristics of an open-jet acoustic wind tunnel are of key importance on measurements of aeroacoustics. The effects of thickness, spreading angle and strength of shear layer on acoustic propagation and source localization are investigated through the mean/spreading shear layer with a self-similar velocity distribution. Based on the shear flow, the acoustic propagation is computed by the linearized Euler equations via a source term, and then source localization is obtained from beamforming technique combined with the theory of Amiet. Results show that the numerical method can precisely capture the refraction and reflection after sound traversing shear layer. The thickness, spreading angle and strength of the shear layer exerts little effects on the refracted region where sound wave nearly vertical incident, while mainly influence the corresponding up/downstream region in terms of phase change. Increment of thickness, spreading angle and strength of the shear layer increases the acoustic difference between the shear layer with and without thickness, and produces a larger error of source localization downstream of the actual position.

This paper investigates the effects of rotorcraft design and operating parameters on trailing-edge noise. A rotor trailing-edge noise prediction method is first developed where the aerodynamics and the turbulence wall pressure spectrum near the trailing edge on airfoils are predicted by a combination of the standard blade element momentum theory , a viscous boundary-layer panel method, and a recently developed empirical wall pressure spectrum model. The coordinate transformations are combined with the Amiet model to predict far-field noise. Compared to experimental data, the validation of this method demonstrates its advantages and validity for airfoil and rotorcraft broadband noise predictions. Then, this method is used to study the effects of rotorcraft design and operating parameters on rotor trailing-edge noise. It is found that helicopter broadband noise scales with the 4.5th to 5.0th power of the tip Mach number in which the range is determined by the typical helicopter collective pitch angle in operation. Detailed trend analyses of noise levels as a function of frequency are presented in terms of the collective pitch angle, twist angle, rotor solidity, rotor radius, disk loading, and number of blades. It is found that the collective pitch angle, twist angle, and chord length make noticeable impacts on low- and midfrequency noise. Finally, a semianalytic model is presented to predict the directivity and geometric attenuation of rotor trailing-edge noise.

A new analytic result in acoustics called “Formulation 1B,” proposed by Farassat, is used to compute the loading noise from an unsteady surface pressure distribution on a thin airfoil in the time domain. This formulation is a new solution of the Ffowcs Williams-Hawkings equation with the loading source term. The formulation contains a far field surface integral that depends on the time derivative and the surface gradient of the pressure on the airfoil, as well as a contour integral on the boundary of the airfoil surface. As a first test case, the new formulation is used to compute the noise radiated from a flat plate, moving through a sinusoidal gust of constant frequency. The unsteady surface pressure for this test case is analytically specied from a result based on linear airfoil theory. This test case is used to examine the velocity scaling properties of Formulation 1B and to demonstrate its equivalence to Formulation 1A of Farassat. The new acoustic formulation, again with an analytic surface pressure, is then used to predict broadband noise radiated from an airfoil immersed in homogeneous, isotropic turbulence. The results are compared with experimental data previously reported by Paterson and Amiet. Good agreement between predictions and measurements is obtained. Finally, an alternative form of Formulation 1B is described for statistical analysis of broadband noise.

Purpose Micro organizational behavior – an individual level of analysis (i.e. motivation, personality, attitudes, learning, etc.). Meso organizational behavior – team/group level of analysis (i.e. communication, team dynamics, power, politics, etc.). Macro organizational behavior – an organizational level of analysis (i.e. strategy, structure, culture, control, etc.). Marketplace or external environment (PESTEL analysis). Research methodology The research was conducted by a consultant in the role of a participant-observer. Case overview/synopsis The focus of the case is a disguised nonprofit organization, the American-Netherlands Foundation (AmNet), based in Chicago. The organization faced leadership and organizational challenges related to conflicting strategic and operational priorities among the board of trustees, the president and staff. An unexpected contribution of $750,000 increased the salience of these differences. The case provides students an excellent opportunity to apply their analytical skills and knowledge gained in a management and business course. Complexity academic level Organizational behavior; organizational design; organizational development; and organizational theory. Levels – upper-level undergraduate through first-year MBA students.

La soufflante de la nouvelle génération de moteurs Snecma est caractérisée par des pales de rotor aux bords de fuite épais, ainsi que par un OGV hétérogène intégrant les bras supports.L’objectif de cette thèse est de caractériser l’influence de ces innovations technologiques sur la génération des sources et le rayonnement sonore dans la manche secondaire liés à l’interaction du sillage du rotor avec l’OGV. Ce mécanisme est principalement responsable des émissions tonales et à large bande qui sont traitées indépendamment. D’une part, une simulation URANS de l’étage rotor-stator fournit les sources déterministes sur le stator hétérogène ainsi que le champ sonore dans la manche traversée par les bras supports. L’extension de modèles acoustiques permet d’accéder au spectre de raies obtenu soit en propageant les sources par un modèle fondé sur le principe de l’analogie acoustique, soit directement à partir du champ sonore issu de la CFD. Il est alors montré que l’hétérogénéité du stator induit l’émergence de la raie du fondamental, et que les bras supports engendrent une onde stationnaire dans la manche secondaire.D’autre part, la simulation d’un canal complet du rotor avec une approche ZDES permet d’accéder aux perturbations turbulentes du sillage. Ces dernières alimentent un code acoustique fondé sur la théorie d’Amiet permettant de prévoir le bruit à large bande rayonné en conduit. Bien que plus coûteuse, la ZDES permet de s’affranchir des hypothèses restrictives et du calibrage délicat des modèles de turbulence homogène isotrope en fournissant des données directement exploitables, conduisant ainsi à des estimations plus précises.L’ensemble des simulations numériques et des prévisions acoustiques est validé grâce aux mesures issues d’une campagne d’essais au banc RACE
Modern turbofans are characterized by rotor blades with large chords, as well as heterogeneous OGV with mechanical struts integrated.The aim of this thesis is to characterize the impact of these technological innovations on sources generation and sound radiation in the bypass duct due to the interaction of the rotor wakes with the OGV. This mechanism is mainly responsible in tonal and broadband noise emissions which are dealt separately.On one hand, a URANS computation of the rotor-stator row provides the periodic sources on the heterogeneous stator as well as the sound field in the bypass duct crossed by the struts. The expansion of sound models allows to access to the tonal spectra obtained either by propagating sources thanks to a model based on the acoustic analogy principle, or by the sound field directly issued from the CFD. Then, it is shown that the stator heterogeneity induces the appearance of the fundamental tone, and that the struts lead to standing waves in the bypass duct.On the other hand, the simulation of a complete rotor channel with a ZDES approach provides the turbulent wakes. These erturbations feed an acoustic code based on the Amiet theory to predict the broadband noise radiated in the bypass duct. Despite the cost, ZDES stays clear of restrictive assumptions and sensitive calibration of isotropic homogeneous turbulence models by providing data directly workable, leading to more accurate predictions. Each of numerical simulations and acoustic predictions is validated thanks to the measurements performed in the RACE test rig

This chapter continues the examination of the special features of artifacts by discussing their place within existing essentialist and anti-essentialist frameworks. It will be argued that prominent essentialist treatments of artifacts, such as those proposed by Amie Thomasson, Simon Evnine, and Lynne Rudder Baker, are susceptible to the concern that they exaggerate the creative and discriminating power of human intentions. Existing anti-essentialist frameworks, however, tend to trace the ascriptions of modal features to objects back to our semantic, inferential, or explanatory practices and are therefore also not particularly well suited to capture the primarily practical and action-based orientation of our engagement with the realm of artifacts. For the time being, the special case of artifacts eludes an entirely satisfactory treatment and must await the further development and refinement of suitable essentialist and anti-essentialist frameworks before the status of artifacts within a hylomorphic ontology can be fully resolved.

In Transmitted Wounds, Amit Pinchevski explores the ways media technology and logic shape the social life of trauma both clinically and culturally. Bringing media theory to bear on trauma theory, Pinchevski reveals the technical operations that inform the conception and experience of traumatic impact and memory. He offers a bold thesis about the deep association of media and trauma: media bear witness to the human failure to bear witness, making the traumatic technologically transmissible and reproducible. Taking up a number of case studies--the radio broadcasts of the Eichmann trial; the videotaping of Holocaust testimonies; recent psychiatric debates about trauma through media following the 9/11 attacks; current controversy surrounding drone operators' post-trauma; and digital platforms of algorithmic-holographic witnessing and virtual reality exposure therapy for PTSD--Pinchevski demonstrates how the technological mediation of trauma feeds into the traumatic condition itself. The result is a novel understanding of media as constituting the material conditions for trauma to appear as something that cannot be fully approached and yet somehow must be. While drawing on contemporary materialist media theory, especially the work of Friedrich Kittler and his followers, Pinchevski goes beyond the anti-humanistic tendency characterizing the materialist approach, discovering media as bearing out the human vulnerability epitomized in trauma, and finding therein a basis for moral concern in the face of violence and atrocity. Transmitted Wounds unfolds the ethical and political stakes involved in the technological transmission of mental wounds across clinical, literary, and cultural contexts.

Some forms of literature interfere with the workings of the literate brain, posing a challenge to readers of all kinds. This book argues that they pose as much of a challenge to the way states conceptualize language, culture, and community. Drawing on a wealth of evidence, from Victorian scholarly disputes over the identity of the English language to the constitutional debates about its future in Ireland, India, and South Africa, and from quarrels over the idea of culture within the League of Nations to UNESCO’s ongoing struggle to articulate a viable concept of diversity, it brings together a large group of legacy writers, including T. S. Eliot, James Joyce, and Rabindranath Tagore, putting them in dialogue with each other and with the policymakers who shaped the formation of modern states and the history of internationalist thought from the 1860s to the 1940s. The second part of the book reflects on the continuing evolution of these dialogues, showing how a varied array of more contemporary writers from Amit Chaudhuri, J. M. Coetzee, and Salman Rushdie, to Antjie Krog, Arvind Krishna Mehrotra, and Es’kia Mphahlele cast new light on a range of questions that have preoccupied UNESCO since 1945. At once a novel contribution to institutional and intellectual history and an innovative exercise in literary and philosophical analysis, Artefacts of Writing affords a unique perspective on literature’s place at the centre of some of the most fraught, often lethal public controversies that defined the long-twentieth century and that continue to haunt us today.

This chapter addresses the existence and nature of fictional entities. It identifies two distinct conditions sufficient for the existence of fictional entities, each of which is grounded by a reference-fixing rule of fiction institutions. One of these rules describes conditions sufficient for the existence of fictional entities that are not constituted by anything, while the other describes conditions sufficient for the existence of fictional entities that are constituted by other things. It identifies the metaphysical dependence base for the existence of fictional entities and argues that this does not include anything metaphysically mysterious. It then describes the nature of fictional entities and their identity and individuation conditions. Finally, it compares the account fictional entities provided with that of Amie Thomasson and argues that, despite obvious similarities, there are fundamental differences between the accounts.

Amie Thomasson argues that ontology is easy. That there are tables (e.g.) is settled by a mixture of conceptual analysis—to discover under what conditions the concept ‘table’ is appropriately deployed—and straightforward empirical observation—looking in my kitchen to see that those conditions are met. There is, then, no distinctively metaphysical work to be done in settling whether there are tables, according to Thomasson. This paper agrees with Thomasson that it is easy to establish that tables exist and gives a two-dimensionalist defense of this claim. However, it argues that a distinctively metaphysical question remains: what must the world be like to make it the case that tables exist? It defends this view against objections from Thomasson, and draws out some morals concerning the project of ontology.

Digital platforms continue to contribute to the global economy by enabling new forms of value creation. Whereas the Information Systems literature is dominated by digital platform research, less is said about Application Programming Interfaces (APIs), the engine behind digital platforms. More so, there is a dearth in the literature on how developing economy firms create value through API integration. To address these research gaps, the author conducted a case study on DigMob (Pseudonym), a digital firm that focuses on the sale of indigenous African music to understand how it created value through API integration. Based on Amit and Zott's value creation model, the findings suggest that DigMob's value creation occurs on a broader value network comprising suppliers (e.g., payment service providers) and customers. For instance, DigMob generated value through the API-enabled platform by ensuring that music lovers purchase their preferred songs at competitive prices. DigMob has also been able to increase their revenue and brand image. Similarly, musicians have been able to rake substantial amounts of money through the sales of their music on the platform.

The chapter considers whether dance works, if they are norm-types, are creatable given that types are conventionally understood to be eternally existing abstracta. It explores whether an account of dance creation as discovery is plausible, critically examining the adaptability to dance of Julian Dodd’s defence of a Platonist ontology of musical works. Problems Dodd raises concerning the putative creatability of indicated types prompts discussion of alternative views, including Amie Thomasson’s arguments that multiple works are abstract artefacts. The chapter critically considers also a simple nominalist view of dance works as sets of performances, and sketches a fictionalist ontology of dance works (following Andrew Kania’s similar discussion of musical works). The fictionalist leanings of some dance discourse critical of the idea of the work is highlighted, and a claim made for the reality of dance works as social objects.

An influential critique of ontology, traditionally linked to Rudolf Carnap, logical empiricism, and verificationism, has it that ontological questions and statements are meaningless. In recent years, Amie Thomasson has revived this Carnapian critique, albeit in a non-verificationist version. This chapter argues that the meaningfulness of ontological statements can be vindicated by appealing to considerations compatible with Thomasson’s Carnapian approach. Two possible avenues are explored. The first is that of specifying the assertibility conditions of ontological statements like ‘There are Fs’, by providing an adequate rule of use. The second is that of spelling out the truth-conditions of the same ontological statements by means of a T-schema where the right-hand side is a sentence formulated in a language specifically introduced for doing ontology—what several authors call ‘Ontologese’. It is proposed that Ontologese be introduced as a bona-fide Carnapian framework, and this option is defended against a number of objections.

Modern French town planning discourse was predicated on the idea that better architecture made for better, happier citizens, with rational architectural principles as the means to a fully realised modernity. After 1968, French filmmakers looked to the suburban new towns to voice the ambiguities and contradictions of rapid urbanisation. In Le Chat (Granier-Deferre, 1972), an ageing couple enter a downward social and psychological spiral as new high-rise construction menaces their decrepit suburban villa. The rough-and-ready La Ville bidon (Jacques Baratier, 1976) shows the struggle of junkmen and their marginalised families to resist expropriation at the hands of a town council that aims to develop a new town on a massive dumpsite. A spoof of streamlined post-modern living, Le Couple témoin (William Klein, 1978) parodies new town rhetoric under the guise of social experiment. The chapter concludes with a double reading of Eric Rohmer’s Les Nuits de la pleine lune (1984) and L’Ami de mon amie (1987) which by turns laud the new towns for their blend of leisure and work and deride their programmed aspect. Dysphoric and euphoric elements of suburban living are related to class-based investments and to the elusive prospect of happiness.

In January 1957 the military and colonial government accepted a master plan drawn up by the anthropologist Jean Servier to undertake Opération Pilote in the Chelif region, the biggest counterinsurgency (COIN) experiment of the Algerian War. The arrival of Salan and Indochina specialists in command accelerated the adoption of the doctrine of revolutionary warfare, that victory over the FLN could not be achieved by conventional ‘big’ force operations, but only through winning over the indigenous population. The catastrophic failure of counterinsurgency in Kabylia in late 1956 diverted attention to the Chelif where a dispersed population was seen as advantageous to COIN operations. Servier’s plan was linked to the revival of Lucien Paye’s communal reform of 1945 to 1948, seen as the key reform to retain Algérie française. By late 1956 the colonial government and military had rapidly lost control of the Dahra and Ouarsenis mountains, a collapse signalled by the evacuation of isolated colons, and the aim was to ‘reconquer’ the interior through driving the ALN and its OPA structures from each douar, and replacing it by ‘djemâa amie’ that could form the core of future rural municipalities in which peasants could take on board their own local government and auto-defense. Unable to guarantee open elections Opération Pilote aimed to secretly train future douar leaders in the psychological warfare centre at Arzew.

The mechanisms of noise generation due to the turbulent flow around an airfoil are complex phenomena. In this paper, a prediction method of the broadband noise is presented then validated. The aim of this work is to develop tools of noise prediction in turbomachinery engaged by the laboratory since several years. The modeling presented is based on the unsteady aerodynamic linearized theory of an airfoil. An acoustic calculation based on the formulation of Amiet determines the far field acoustic power spectral density produced by an airfoil. It shows the importance of the noise due to the interaction of incident turbulence flow with the leading edge. The results obtained are compared with the experimental results available in the literature.

An extended version of the previously presented linearized one-dimensional turbomachinery performance model is described. The current version of the model is capable of performing forced response and flutter simulations on several stationary and/or rotating bladerows. The amplitude of the perturbation is assumed small thus impact of the perturbations of several sources may be superimposed. The distortion propagation analysis may be performed in the early stages of the design process, or whenever a quick solution is desirable, having only minimal information about the studied geometry. The approach has a block structure, where each block represents a bladed passage or the empty space between. The blocks contain linearized gas relations that relate the gas state to known changes of enthalpy, entropy and momentum. The blade blocks are represented using the extended semi-actuator disk theory, where the flow inside the passage assumed to be one-dimensional [9]. The model considers frequency scattering for the rotating bladerows and is also using a complete package of linearized loss- and deviation correlations, providing more realistic results. The approach extends the previously presented methods by Amiet [2], [3] and Kaji&Okazaki [4], [5], being capable to handle harmonic distortions of various wavelength-to-chord ratios. Minimal assumptions are made about the studied geometry and nature of the gas, allowing to perform unsteady flow analysis not only on the idealized cases, but on more complex, realistic geometry. Appropriate non-reflecting boundary conditions are applied at the boundaries of each block, using the hyperbolic characteristic theory, thus facilitating multi-blaredow domains setup and allowing running more complex cases, involving both forced response and flutter. A number of idealized cases presented by Amiet and Kaji & Okazaki are reproduced to validate the model against the reference data, where a good comparison is achieved. The approach is also tested on the HP compressor of modern design for forced response simulations. Several multi-bladerow cases are also studied.

Solid handling pumps are used in Sewage applications, Slurry transportation, transportation of floating solids etc. Many manufacturers supply such solid handling pumps for different applications. Few of the manufactures have test facility to study the impact of solid particles on overall performance of pump. It is then possible to experimentally bring out effect of solid size, its concentration etc. on overall performance. The literature is available for several such tests conducted by pump manufacturers. In absence of experimental test facility for solid handling pumps, a numerical approach was proposed to investigate the effect of solid particles on the pump performance. Commercially available CFD tool was used to carry out numerical experiments. A standard pump in production was chosen as a test case. It was ensured that experimental test results of similar size pump are available in literature. The work presented here is the extension of the work done by Gupta Amit for a solid handling impeller [8]. The similar impeller assembled with casing for solid handling pump was analyzed first to compute the performance of whole pump with clear water. This was compared with test results available from factory tests conducted experimentally with clear water. The same geometry was then analyzed using particle tracking drag models available in the software given the new boundary conditions of solid additions. Results from the numerical experiments, including effect of particle size, their concentrations etc were brought out. The particle trajectory from impeller entry to exit of casing gave idea as how particles travel in solid handing pumps. The computational results were compared with the ones presented in the Pump Handbook by Karassik. The software results were useful in getting additional information on loss in impeller and casing separately. This gives a clue to as which component needs improvement. The paper describes the approach used in numerical experiments and the results thereof.

Az elmúlt évtizedben már számos kutatás bizonyította, hogy a pedagógusok megváltozott feladatai és szerepei, a módszertani kultúra és a komplex szemlélet a digitális kompetencia fejlesztésével párhuzamosan megjelenik (Fehér, 1999; Kirschner-Woperies, 2003; Law, Chow és Yuen, 2005). A tanítási-tanulási folyamat résztvevőiként a pedagógusok is részesei a rendkívüli iramban változó lehetőségeknek, melyek az iskola különböző „valós és virtuális” terein egyre inkább biztosítottá válnak (UNESCO, 2011). 2020 márciusában 6 a koronavírus-járvány miatt bevezetett digitális munkarend által – korábban még nem tapasztalt módon – aktuálissá vált mindaz, amit a „távoktatás”, „digitális oktatás”, „otthontanulás” és szinonimáik képviseltek. A pedagógusok, diákok és szülők egyik napról a másikra kerültek át az osztálytermi környezetből a digitális platformok világába, megváltoztatva szerepeiket, feladataikat és kompetenciahatáraikat. Felmérésünk azzal a céllal készült, hogy feltárja a tanítók hogyan igyekeztek megtalálni a tantárgyi specialitásnak, informatikai tudásuknak, rendelkezésre álló eszközeiknek, a diákoknak és a szülőknek leginkább adekvát megoldásokat. Kutatásunkban kvantitatív módszert alkalmazva, online kérdőíves vizsgálattal mértük fel az 1-6. osztályban tanító pedagógusok véleményét és gyakorlatát a digitális munkarendben történő oktatással kapcsolatban (N=71). Előadásunk a tanítók által alkalmazott karanténpedagógiára vonatkozó öszszefüggésekre világít rá a következő aspektusokból: eszközök, internet a távoktatásban, a pedagógusok digitális kompetenciája, a tananyagok küldésének felülete, kapcsolattartás a tanulókkal és szülőkkel. Fókuszba kerültek az alkalmazott digitális platformok és eszközök, azzal a céllal, hogy feltárjuk az elmúlt időszakban aktuális alsó tagozatos oktatás és nevelés főbb aspektusait. A digitális munkarend, valamint az online eszközök kiválasztásának és kipróbálásának tanítói tapasztalatait is vizsgáltuk az önértékelésen alapuló tanítói digitális kompetenciák feltárása mellett. A kapott leíró statisztikai elemzések megerősítik, hogy a digitális munkarenddel kialakuló távolléti oktatási struktúra rendszerezettségében, illetve következetes használatában plasztikus eltérések jelentkeztek. Példaként említhető a kapcsolattartási mintázatok egyenetlensége és a formális (Kréta)/informális kapcsolattartási struktúra (Messenger/Facebook csoport) használatának eltérő megoszlása. Konkrét számadatokkal mérve a szülőkkel való kapcsolattartásban kiemelkedett az egyéb lehetőségek mellett a Facebook csoport (59%), és a Messenger (53%) használata a formális platformként említett Krétával (22%) szemben. Összefoglalva, az eredmények hozzájárulhatnak az általános iskolákban működő online oktatás gyakorlatának megismeréséhez, a pedagógiai praxis lehetőségeinek bővítéséhez, ugyanakkor megerősítjük Lévai (2016) felvetését is, miszerint a pedagógusok felelőssége számottevő és árulkodó abból a szempontból is, hogy mit mutatnak róluk digitális lábnyomaik, illetve az online elérhető felületek. ---- Lower-primary-school teachers’ digital educational experience: possibilities in lockdown induced pedagogy ----- The past couple decades have seen a parallel change in teachers’ tasks and roles, methodologies, educational approaches and the development of their digital competences (Fehér, 2009; KirschnerWoperies, 2003; Law, Chow and Yuen, 2005). Also teachers as participants of the teaching-learning process experience the rapid evolution of the possibilities in the real-life and virtual platforms of school (UNESCO, 2011). In March, 2020 unprecedentedly digital education was launched due to the coronavirus pandemic and “distance education”, “digital education”, “home schooling” (at present regarded as synonyms) had become reality. All at once, teachers, students and parents were transmitted from real-life classrooms into the world of virtual platforms, which modified their roles, tasks and competence boundaries. Our survey was conducted to explore how lower-primary-school teachers experimented to find the most adequate solutions related to the issues of their teaching areas and digital knowledge. Also, we aimed to detect the most characteristic challenges that the respondent teachers had to face during the lockdown period online education processes. Our quantitative research was conducted to collect data via an online questionnaire to elicit beliefs and practices of lower-primary-school teachers of 1-6-forms regarding their work during lockdown digital education (N=71). The main focus of our research was the interrelationships of lockdown induced pedagogy from the following aspects: tools in digital education, teachers’ digital competence (based on self-assessment), the platforms of sharing teaching contents and of contacting students and parents. The focal points of our study were the applied digital platforms and tools and to gain insights into the teachers’ digital competences based on their self-evaluation. We also explored the respondent teachers’ choices and experience regarding the online tools of digital education. The results of descriptive statistics showed that there were differences in the structure and consistent use of digital education during the lockdown. As an example, the distribution of the formal Kréta platform and other informal ones (Messenger/Facebook group) is uneven in terms of contact between teachers and parents. Also, the Facebook group (59%) and Messenger (53%) platforms outnumber the use of Kréta (22%) during teacher-parent communication. In sum, our results can contribute to a better understanding of the practice of online education at primary-schools, and also to the extension of the teaching repertoire in 1-6 forms. These findings are also compatible with Lévai’s (2016) results, that is teachers’ digital footsteps and the online platforms that they use can reveal a lot about them, which is a great professional responsibility.