A Methodology for Generative Spelling Correction via Natural Spelling Errors Emulation across Multiple Domains and Languages

Modern large language models demonstrate impressive capabilities in text generation and generalization. However, they often struggle with solving text editing tasks, particularly when it comes to correcting spelling errors and mistypings. In this paper, we present a methodology for generative spelling correction (SC), which was tested on English and Russian languages and potentially can be extended to any language with minor changes. Our research mainly focuses on exploring natural spelling errors and mistypings in texts and studying the ways those errors can be emulated in correct sentences to effectively enrich generative models' pre-train procedure. We investigate the impact of such emulations and the models' abilities across different text domains. In this work, we investigate two spelling corruption techniques: 1) first one mimics human behavior when making a mistake through leveraging statistics of errors from particular dataset and 2) second adds the most common spelling errors, keyboard miss clicks, and some heuristics within the texts. We conducted experiments employing various corruption strategies, models' architectures and sizes on the pre-training and fine-tuning stages and evaluated the models using single-domain and multi-domain test sets. As a practical outcome of our work, we introduce SAGE(Spell checking via Augmentation and Generative distribution Emulation). It is a library for automatic generative SC that includes a family of pre-trained generative models and built-in augmentation algorithms.Comment: to appear in EACL 202

Secure Multicast with Source Authentication for the Internet of Things

Sakernas Internet är ett snabbt växande område av avancerad teknik och forskning. Dess säkerhet är avgörande för tillförlitligheten och tryggheten av framtida dagliga kommunikationer. DTLS protokollet är ett standardprotokoll för att garantera säkerheten för unicast kommunikation. En DTLS rekord lager tillägg för multicast i begränsade miljöer håller på att utformas för att garantera säkerheten för multicast. Däremot nuvarande förslag av DTLS baserad multicast ger inte en sådan viktig egenskap som källäkthet för de överförda uppgifterna. Dessutom är handslag lagret utformat för att bara etablera parvisa nycklar, och därmed finns det inget sätt att distribuera och hantera gruppnycklar heller. De två ovan nämnda nackdelar blir de primära målen för designen för examensarbetet. Detta examensarbete genomförs i samarbete med Philips. I examensarbetet, formulerar vi kraven för att säkerställa multicast i en begränsad miljö baserad på företagets utomhusbelysning scenariot med en centraliserad förtroende modell. Vi utvärderar olika autentiseringssystem av källor och 4 nyckelhanteringsprotokoll med avseende på de formulerade kraven. Vi väljer två autentiseringssystem och använder dem på vårt scenario. Som resultat konstruerar vi en förlängning av DTLS baserad multicast med stöd av ECDSA signaturen för källautentisering och utvecklar en prototyp implementering. Förutom det, vi bestämmer kryptografiska primitiver för TESLA systemet och anpassar det system som ska användas för den periodiska kommunikationsmodellen. Till slut, konstruerar vi en lätt och flexibel lösning för gruppnyckelhantering för att dela ut gruppnycklar och allmänna nycklar från den pålitliga myndigheten.The Internet of Things is a rapidly evolving field of high-end technology and research. Its security is vital to the reliability and safety of the future everyday communications. The DTLS protocol is a default protocol to assure security for unicast communication. A DTLS record layer extension for multicast in constrained environments is being designed to assure security for multicast. However, currently proposed DTLS-based multicast does not provide such an essential property as source authenticity for the transmitted data. Moreover, handshake layer is designed to establish pairwise keys only, and hence, there is no way to distribute and manage group keys either. The two aforementioned downsides become the primary objectives of the design for the thesis. This thesis is conducted in collaboration with Philips. In the thesis, we formulate requirements to secure multicast in constrained environment based on the company's outdoor lighting scenario with centralized trust model. We evaluate various source authentication schemes and 4 key management protocols with regards to the formulated requirements. We select two authentication schemes and apply them to our scenario. As a result we design an extension of DTLS based multicast with support of ECDSA signature for source authentication and we develop a prototype implementation. Besides that, we determine cryptographic primitives for the TESLA scheme and adapt the scheme to be used for periodic communication pattern. Further, we design a lightweight and flexible group key management solution to distribute group keys and public keys by the trusted authority

Secure Multicast with Source Authentication for the Internet of Things

Sakernas Internet är ett snabbt växande område av avancerad teknik och forskning. Dess säkerhet är avgörande för tillförlitligheten och tryggheten av framtida dagliga kommunikationer. DTLS protokollet är ett standardprotokoll för att garantera säkerheten för unicast kommunikation. En DTLS rekord lager tillägg för multicast i begränsade miljöer håller på att utformas för att garantera säkerheten för multicast. Däremot nuvarande förslag av DTLS baserad multicast ger inte en sådan viktig egenskap som källäkthet för de överförda uppgifterna. Dessutom är handslag lagret utformat för att bara etablera parvisa nycklar, och därmed finns det inget sätt att distribuera och hantera gruppnycklar heller. De två ovan nämnda nackdelar blir de primära målen för designen för examensarbetet. Detta examensarbete genomförs i samarbete med Philips. I examensarbetet, formulerar vi kraven för att säkerställa multicast i en begränsad miljö baserad på företagets utomhusbelysning scenariot med en centraliserad förtroende modell. Vi utvärderar olika autentiseringssystem av källor och 4 nyckelhanteringsprotokoll med avseende på de formulerade kraven. Vi väljer två autentiseringssystem och använder dem på vårt scenario. Som resultat konstruerar vi en förlängning av DTLS baserad multicast med stöd av ECDSA signaturen för källautentisering och utvecklar en prototyp implementering. Förutom det, vi bestämmer kryptografiska primitiver för TESLA systemet och anpassar det system som ska användas för den periodiska kommunikationsmodellen. Till slut, konstruerar vi en lätt och flexibel lösning för gruppnyckelhantering för att dela ut gruppnycklar och allmänna nycklar från den pålitliga myndigheten.The Internet of Things is a rapidly evolving field of high-end technology and research. Its security is vital to the reliability and safety of the future everyday communications. The DTLS protocol is a default protocol to assure security for unicast communication. A DTLS record layer extension for multicast in constrained environments is being designed to assure security for multicast. However, currently proposed DTLS-based multicast does not provide such an essential property as source authenticity for the transmitted data. Moreover, handshake layer is designed to establish pairwise keys only, and hence, there is no way to distribute and manage group keys either. The two aforementioned downsides become the primary objectives of the design for the thesis. This thesis is conducted in collaboration with Philips. In the thesis, we formulate requirements to secure multicast in constrained environment based on the company's outdoor lighting scenario with centralized trust model. We evaluate various source authentication schemes and 4 key management protocols with regards to the formulated requirements. We select two authentication schemes and apply them to our scenario. As a result we design an extension of DTLS based multicast with support of ECDSA signature for source authentication and we develop a prototype implementation. Besides that, we determine cryptographic primitives for the TESLA scheme and adapt the scheme to be used for periodic communication pattern. Further, we design a lightweight and flexible group key management solution to distribute group keys and public keys by the trusted authority

Real-time assessment of hypnotic depth, using an EEG-based brain-computer interface: a preliminary study

Objective: Hypnosis can be an effective treatment for many conditions, and there have been attempts to develop instrumental approaches to continuously monitor hypnotic state level (“depth”). However, there is no method that addresses the individual variability of electrophysiological hypnotic correlates. We explore the possibility of using an EEG-based passive brain-computer interface (pBCI) for real-time, individualised estimation of the hypnosis deepening process. Results: The wakefulness and deep hypnosis intervals were manually defined and labelled in 27 electroencephalographic (EEG) recordings obtained from eight outpatients after hypnosis sessions. Spectral analysis showed that EEG correlates of deep hypnosis were relatively stable in each patient throughout the treatment but varied between patients. Data from each first session was used to train classification models to continuously assess deep hypnosis probability in subsequent sessions. Models trained using four frequency bands (1.5–45, 1.5–8, 1.5–14, and 4–15 Hz) showed accuracy mostly exceeding 85% in a 10-fold cross-validation. Real-time classification accuracy was also acceptable, so at least one of the four bands yielded results exceeding 74% in any session. The best results averaged across all sessions were obtained using 1.5–14 and 4–15 Hz, with an accuracy of 82%. The revealed issues are also discussed

Features of the course of COVID-19 in patients with type 2 diabetes mellitus

Aim. To identify the features of the course of COVID-19 in patients with type 2 diabetes mellitus (T2DM), depending on the intake of hypoglycemic therapy at the prehospital stage, in conjunction with the functional state of the kidneys. Materials and methods. A retrospective analysis of 291 case histories of patients with COVID-19 and T2DM hospitalized in the infection department of Semashko Regional Clinical Hospital from January to December 2021, including the main clinical and laboratory parameters. Results. Among hospitalized patients with COVID-19, patients with T2DM had a higher mortality rate. An analysis of the case histories of deceased patients with COVID-19 and T2DM showed that at admission, body mass index (BMI), C-reactive protein, and creatinine were higher than those of survivors and amounted to BMI – 33 [30; 39] and 33 [28; 36] kg/m3; p=0.039, C-reactive protein – 77 [47.5; 106.0] and 57 [27.0; 89.0] mg/l; p=0.015, in terms of creatinine level – 89 [70.0; 144.0] and 82 [66.0; 101.0] µmol/l; p=0.039, respectively. It was found that in the second week of hospitalization in the group of deceased patients with COVID-19 and T2DM, the creatinine level was statistically significantly higher than in surviving patients and amounted to 94.5 [71.5; 141.0] and 72.5 [57.0; 88.0] µmol/L; p0.001, respectively. The probability of death in hospitalized patients with type 2 COVID-19 and T2DM depended on BMI and creatinine levels at the second week of hospitalization. Patients with prehospital correction of hyperglycemia dipeptidyl peptidase-4 inhibitors (iDPP-4)/ glucagon-like peptide-1 receptor agonists (agGLP-1)/ sodium-glucose co-transporter 2 inhibitors (iSGLT-2) had significantly lower creatinine levels at week 2 of hospitalization. Conclusion. In patients with moderate to severe COVID-19 with concomitant T2DM, special attention should be paid to the combination of high BMI and creatinine in the second week of hospitalization, which is a prognostically unfavorable predictor of death in such patients

Search for intermediate-mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo

International audienceIntermediate-mass black holes (IMBHs) span the approximate mass range 100−105 M⊙, between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∼150 M⊙ providing direct evidence of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200 M⊙ and effective aligned spin 0.8 at 0.056 Gpc−3 yr−1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc−3 yr−1.Key words: gravitational waves / stars: black holes / black hole physicsCorresponding author: W. Del Pozzo, e-mail: [email protected]† Deceased, August 2020