Mariana Atanasova

EUPHEMIA, the Pan-European day-ahead electricity market-coupling algorithm, operates in a centralized manner that restricts independent auditability and has been characterized as pseudo-transparent. We propose a blockchain-based architecture that improves the transparency and verifiability of the market-coupling process while preserving participant confidentiality. It combines off-chain computation with selective on-chain publication and treats the three principal data categories of the EUPHEMIA pipeline separately: order books, network constraints, and clearing outputs. Zero-knowledge proofs utilizing zk-STARKs are employed to verify the integrity of the order book aggregation process and specific network-constraint sub-processes, whereas Merkle commitments ensure tamper-evident anchoring of publicly disclosed data. zk-STARKs are selected over CRS-based alternatives to eliminate the trusted-setup governance overhead associated with EUPHEMIA’s multi-jurisdictional structure. The estimated AIR trace size reaches approximately 2,225,000 rows in the worst-case NEMO (EPEX SPOT) scenario. A correction proof generated by the Regional Coordination Centre (RCC) requires an AIR of 641 trace rows when a binding network constraint exceeds its threshold during the review of Transmission System Operator (TSO) submissions. This trace size corresponds to an estimated proving time of 1 to 30 s based on reported STARK prover throughput. End-to-end verification of welfare maximization remains infeasible due to the lack of a complete public algorithm specification. Preliminary calibrated estimates are provided, and full empirical benchmarking remains as future work.

Supply chain traceability often fails in practice because relevant records are scattered across production, warehouse, transport, laboratory, and document systems. When a recall or audit is needed, firms must manually collect and reconcile evidence from many sources. Existing standards and blockchain platforms address parts of this problem, but prior work still reports recurring weaknesses in governance, confidentiality management, interoperability, and performance measurement. This paper presents a governance-aware, privacy-preserving, event-driven conceptual model for supply chain traceability. The model uses five event types—Create, Transform, Transfer, Verify, and Recall—linked through explicit lineage. It stores compact signed event headers on-ledger and anchors detailed off-ledger payloads and governance policy text through hashes. It also links data-sharing choices to consortium governance, defines validation invariants, embeds key performance indicators, and produces two regulator-ready outputs: a product passport and an audit pack. The contribution is a standards-informed conceptual artifact that integrates event semantics, provenance reconstruction, selective disclosure, governance, validation, performance measurement, and regulator-ready outputs in one cross-sector traceability model.

Argon plasma torch sustained by 2.45 GHz electromagnetic wave can be in contact with water surface or penetrate inside the water depending on the wave power. The propagation of the electromagnetic wave sustaining the discharge in water is problematic: the water dielectric permittivity strongly depends on the wave frequency and the temperature and varies between 6 and 86. At wave frequency of 2.45 GHz and room temperature (20 ?C) its value is 80 which leads to very fast decay of the electromagnetic wave. We have studied both theoretically and experimentally the plasma properties and the electrodynamics of the wave propagation when the gas discharge is in contact with water. Depending on the wave power and the gas flow it is possible to produce plasma with low (room) temperature. The plasma is non-equilibrium one with electron temperature much higher than the gas/liquid temperature. Because of this many radicals and chemically active particles can be produced even at low temperature. Depending on the regime of operation this kind of discharges can find various applications for surface treatment, sterilization, surface energy change and others, including temperature sensitive materials and liquids treatment.

The role of the driving field frequency f _d of a cool atmospheric plasma (CAP) is investigated for values around using a two-dimensional fluid numerical model applied to a parallel plate configuration. It is found that keeping the voltage constant the current amplitude roughly scales with ; a tendency that can be understood using a RC circuit model of the plasma-sheath configuration. Moreover, it is seen that the electron density increases faster than the density of the excited species. This implies that plasma heating will increase relatively more than plasma reactivity so that the basic feature of the CAP, to be cool and reactive, will weaken for increasing f _d-values.

A capacitive radiofrequency (RF) discharge at atmospheric pressure is studied by means of a time-dependent, two-dimensional fluid model. The plasma is created in a stationary argon gas flow guided through two perforated electrodes, hence resembling a shower. The inner electrode, the electrode facing the flow entrance, is powered with a frequency of 13.56 MHz, and the outer electrode is grounded. The model solves the mass balance equations for the relevant active species and the electron energy balance equation in conjunction with the Poisson equation for the field sustaining the plasma. The mass balance equations of the active species are calculated using the drift–diffusion–convection approach, thus taking the bulk velocity into account. The velocity field is calculated with the Navier–Stokes module of the Plasimo toolkit. The plasma dynamics is studied in three connected regions; the space between the electrodes, the regions before the powered electrode and the extended region behind the grounded electrode. The effect of the shower holes and the recirculation gas flow on the plasma is examined.

A proper description of the flux of active species generated by cold atmospheric-pressure (AP) plasma jets is of crucial importance for plasma applications. To that end, a 2-D fluid model has been constructed to investigate the effect of the coupling between the plasma kinetics and plasma flow. It is shown that pure-argon cold AP RF plasma jets are not only controlled by diffusion losses but also by convective transport of argon molecular ions Ar2+.

A cool atmospheric pressure non-thermal capactively-coupled RF discharge is studied. It is created between two parallel electrodes – a powered one supplied by 13.56 MHz, and a grounded one. The feed gas argon flows via holes between the electrodes where it is ionized. The plasma torch is studied by means of a time dependent two-dimensional fluid model. A simplified kinetic scheme with four active species is considered, namely argon excited atoms (Ar*), atomic (Ar⁺) ions, molecular (Ar²⁺) ions and electrons (e). The plasma dynamics in the space between the electrodes as well as in the extended region behind the grounded electrode is studied. The effect of the gas flow on the plasma is examined. Constriction of the plasma is induced by the field sustaining the discharge due to the sieve-like structure of the electrodes. As a result of the stationary gas flow the filaments extend beyond the electrodes ensuring a flow of active species in the afterglow.