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Adversarial Attacks on Deep Models for Financial Transaction Records [article]

Ivan Fursov, Matvey Morozov, Nina Kaploukhaya, Elizaveta Kovtun, Rodrigo Rivera-Castro, Gleb Gusev, Dmitry Babaev, Ivan Kireev, Alexey Zaytsev, Evgeny Burnaev
2021 arXiv   pre-print
Machine learning models using transaction records as inputs are popular among financial institutions. The most efficient models use deep-learning architectures similar to those in the NLP community, posing a challenge due to their tremendous number of parameters and limited robustness. In particular, deep-learning models are vulnerable to adversarial attacks: a little change in the input harms the model's output. In this work, we examine adversarial attacks on transaction records data and
more » ... es from these attacks. The transaction records data have a different structure than the canonical NLP or time series data, as neighbouring records are less connected than words in sentences, and each record consists of both discrete merchant code and continuous transaction amount. We consider a black-box attack scenario, where the attack doesn't know the true decision model, and pay special attention to adding transaction tokens to the end of a sequence. These limitations provide more realistic scenario, previously unexplored in NLP world. The proposed adversarial attacks and the respective defences demonstrate remarkable performance using relevant datasets from the financial industry. Our results show that a couple of generated transactions are sufficient to fool a deep-learning model. Further, we improve model robustness via adversarial training or separate adversarial examples detection. This work shows that embedding protection from adversarial attacks improves model robustness, allowing a wider adoption of deep models for transaction records in banking and finance.
arXiv:2106.08361v1 fatcat:l4s5xldrafgater7fv73nl5rme

A Differentiable Language Model Adversarial Attack on Text Classifiers [article]

Ivan Fursov, Alexey Zaytsev, Pavel Burnyshev, Ekaterina Dmitrieva, Nikita Klyuchnikov, Andrey Kravchenko, Ekaterina Artemova, Evgeny Burnaev
2021 arXiv   pre-print
Robustness of huge Transformer-based models for natural language processing is an important issue due to their capabilities and wide adoption. One way to understand and improve robustness of these models is an exploration of an adversarial attack scenario: check if a small perturbation of an input can fool a model. Due to the discrete nature of textual data, gradient-based adversarial methods, widely used in computer vision, are not applicable per~se. The standard strategy to overcome this
more » ... is to develop token-level transformations, which do not take the whole sentence into account. In this paper, we propose a new black-box sentence-level attack. Our method fine-tunes a pre-trained language model to generate adversarial examples. A proposed differentiable loss function depends on a substitute classifier score and an approximate edit distance computed via a deep learning model. We show that the proposed attack outperforms competitors on a diverse set of NLP problems for both computed metrics and human evaluation. Moreover, due to the usage of the fine-tuned language model, the generated adversarial examples are hard to detect, thus current models are not robust. Hence, it is difficult to defend from the proposed attack, which is not the case for other attacks.
arXiv:2107.11275v1 fatcat:ava6j4azlzagfm2ibbcks32n7q

Sergei Pavlovich Strelkov (obituary)
Памяти Сергея Павловича Стрелкова

V.P. Kandidov, Polina S. Landa, M.A. Leontovich, V.S. Fursov, A.A. Kharlamov, V.I. Shmal'gauzen, Ivan A. Yakovlev
1974 Uspehi fiziceskih nauk  
197ά г. Сентябрь Том 114, вып. 1 УСПЕХИ ФИЗИЧЕСКИХ НАУК PERSONALIA 53(92) ПАМЯТИ СЕРГЕЯ ПАВЛОВИЧА СТРЕЛКОВА 2 апреля 1974 г. скоропостижно скончался Сергей Павлович Стрелков, один из старейших профессоров физического факультета Московского государственного университета, заслуженный деятель науки и техники РСФСР. СП. Стрелков родился в 1905 г. в селе Долгоруково Пензенской губернии в семье учителей сельской школы. В 1927 г. он поступил на физико-математический факультет МГУ и прошел путь от
more » ... нта до профессора, заведующего одной из крупнейших кафедр физического факультета. Являясь, наряду с А. А. Андроновым, А. А. Виттом, С. Э. Хайкиным, Г. С. Гореликом и др., одним из ярких представителей научной школы академика Л. И. Мандельштама, Сергей Павлович Стрелков был крупным специалистом в области физики колебаний. Многие задачи, которые ставились и решались в его работах, а также в работах его учеников были вызваны проблемами, возникающими при создании новой авиационной техники. Наиболее характерной особенностью всех научных исследований С. П. Стрелкова является глубокий физический анализ колебательных процессов, происходящих в рассматриваемых системах. Прекрасно владея сложными математическими методами, Сергей Павлович никогда не ограничивался формально-математической стороной дела. Его основной целью было раскрытие физического содержания исследуемых явлений. С. П. Стрелковым было опубликовано свыше пятидесяти научных трудов в различных областях физики и механики. Эти работы посвящены главным образом исследованию автоколебаний в различных механических системах. Сергей Павлович является автором прекрасных учебников по механике и теории колебаний, а также задачника по общему курсу физики. По этим учебникам учились и учатся десятки тысяч студентов университетов. За десять дней до смерти С. П. Стрелков сдал в издательство рукопись нового, значительно переработанного издания своей заслуженно популярной книги по механике. Когда Сергея Павловича спрашивали о том, что нового он внес в свою книгу, он отвечал, что старался прежде всего изложить более нагляднее, убедительнее, доступнее физические принципы механики. Первая научная работа * С. П. Стрелкова, опубликованная в 1933 г., была посвящена исследованию автоколебаний в механической системе (маятник Фроуда). В этой работе дана подробная физическая картина возбуждения автоколебаний в системе с трением скольжения, зависящим от скорости, проведен математический анализ процесса установления стационарной амплитуды, а также приведены результаты экспериментального иссследования. В следующей работе 2 С. П. Стрелковым дан подробный качественный и количественный анализ переходных процессов в ламповом генераторе с двумя колебательными контурами (явление затягивания частоты). Впоследствии это исследование вошло во все учебники по теории нелинейных колебаний. Сергей Павлович Стрелков был одним из основоположников исследований автоколебаний в распределенных системах. Им была полностью решена задача об автоколебаниях в двухпроводной линии с электронной лампой на одном из концов 3 . В своих работах Сергей Павлович успешно использовал строгие нелинейные методы, развиваемые школой Л. И. Мандельштама. Эти методы сущестенно отличались от применявшихся тогда в технике квазилинейных методов анализа автоколебательных систем. В то время казалось, что эти два подхода принципиально исключают друг друга, но дальнейшее развитие обоих направлений показало, что они дополняют друг друга. Большой цикл работ С. П. Стрелкова 4 ~6 посвящен исследованию автоколебаний различных тел в потоке воздуха или жидкости. Сергей Павлович, по-видимому, впер-© Издательство «Наука» \1 УФН, т. 114, вып. 1 «Успехи физических наук», 1974 г.
doi:10.3367/ufnr.0114.197409p.0169 fatcat:vzujxmwfrngile5yperfklwgba

Shared bioinformatics databases within the Unipro UGENE platform

Ivan V Protsyuk, German A Grekhov, Alexey V Tiunov, Mikhail Y Fursov
2015 Journal of Integrative Bioinformatics  
Unipro UGENE is an open-source bioinformatics toolkit that integrates popular tools along with original instruments for molecular biologists within a unified user interface. Nowadays, most bioinformatics desktop applications, including UGENE, make use of a local data model while processing different types of data. Such an approach causes an inconvenience for scientists working cooperatively and relying on the same data. This refers to the need of making multiple copies of certain files for
more » ... workplace and maintaining synchronization between them in case of modifications. Therefore, we focused on delivering a collaborative work into the UGENE user experience. Currently, several UGENE installations can be connected to a designated shared database and users can interact with it simultaneously. Such databases can be created by UGENE users and be used at their discretion. Objects of each data type, supported by UGENE such as sequences, annotations, multiple alignments, etc., can now be easily imported from or exported to a remote storage. One of the main advantages of this system, compared to existing ones, is the almost simultaneous access of client applications to shared data regardless of their volume. Moreover, the system is capable of storing millions of objects. The storage itself is a regular database server so even an inexpert user is able to deploy it. Thus, UGENE may provide access to shared data for users located, for example, in the same laboratory or institution. UGENE is available at: http://ugene.net/download.html.
doi:10.2390/biecoll-jib-2015-257 pmid:26527191 fatcat:sabnkr2g2vhahcfp3dnw5pw6pe

Shared Bioinformatics Databases within the Unipro UGENE Platform

Ivan V. Protsyuk, German A. Grekhov, Alexey V. Tiunov, Mikhail Yu. Fursov
2015 Journal of Integrative Bioinformatics  
SummaryUnipro UGENE is an open-source bioinformatics toolkit that integrates popular tools along with original instruments for molecular biologists within a unified user interface. Nowadays, most bioinformatics desktop applications, including UGENE, make use of a local data model while processing different types of data. Such an approach causes an inconvenience for scientists working cooperatively and relying on the same data. This refers to the need of making multiple copies of certain files
more » ... r every workplace and maintaining synchronization between them in case of modifications. Therefore, we focused on delivering a collaborative work into the UGENE user experience. Currently, several UGENE installations can be connected to a designated shared database and users can interact with it simultaneously. Such databases can be created by UGENE users and be used at their discretion. Objects of each data type, supported by UGENE such as sequences, annotations, multiple alignments, etc., can now be easily imported from or exported to a remote storage. One of the main advantages of this system, compared to existing ones, is the almost simultaneous access of client applications to shared data regardless of their volume. Moreover, the system is capable of storing millions of objects. The storage itself is a regular database server so even an inexpert user is able to deploy it. Thus, UGENE may provide access to shared data for users located, for example, in the same laboratory or institution. UGENE is available at: http://ugene.net/download.html.
doi:10.1515/jib-2015-257 fatcat:pdmvoq7aofe2dbdf5ffvafbopq

Multidrug-Resistant Klebsiella pneumoniae Causing Severe Infections in the Neuro-ICU

Nadezhda K. Fursova, Evgenii I. Astashkin, Olga N. Ershova, Irina A. Aleksandrova, Ivan A. Savin, Tatiana S. Novikova, Galina N. Fedyukina, Angelina A. Kislichkina, Mikhail V. Fursov, Ekaterina S. Kuzina, Sergei F. Biketov, Ivan A. Dyatlov
2021 Antibiotics  
The purpose of this study was the identification of genetic lineages and antimicrobial resistance (AMR) and virulence genes in Klebsiella pneumoniae isolates associated with severe infections in the neuro-ICU. Susceptibility to antimicrobials was determined using the Vitek-2 instrument. AMR and virulence genes, sequence types (STs), and capsular types were identified by PCR. Whole-genome sequencing was conducted on the Illumina MiSeq platform. It was shown that K. pneumoniae isolates of ST14K2,
more » ... ST23K57, ST39K23, ST76K23, ST86K2, ST218K57, ST219KL125/114, ST268K20, and ST2674K47 caused severe systemic infections, including ST14K2, ST39K23, and ST268K20 that were associated with fatal incomes. Moreover, eight isolates of ST395K2 and ST307KL102/149/155 were associated with manifestations of vasculitis and microcirculation disorders. Another 12 K. pneumoniae isolates of ST395K2,KL39, ST307KL102/149/155, and ST147K14/64 were collected from patients without severe systemic infections. Major isolates (n = 38) were XDR and MDR. Beta-lactamase genes were identified: blaSHV (n = 41), blaCTX-M (n = 28), blaTEM (n = 21), blaOXA-48 (n = 21), blaNDM (n = 1), and blaKPC (n = 1). The prevalent virulence genes were wabG (n = 41), fimH (n = 41), allS (n = 41), and uge (n = 34), and rarer, detected only in the genomes of the isolates causing severe systemic infections—rmpA (n = 8), kfu (n = 6), iroN (n = 5), and iroD (n = 5) indicating high potential of the isolates for hypervirulence.
doi:10.3390/antibiotics10080979 fatcat:ef36q4zpnfaofcrcifebmdqnem

Rem Viktorovich Khokhlov (Obituary)
Памяти Рема Викторовича Хохлова

S.A. Akhmanov, N.G. Basov, É.S. Voronin, A.V. Gaponov, Boris B. Kadomtsev, L.V. Keldysh, Anatolii A. Logunov, V.V. Migulin, A.M. Prokhorov, S.M. Rytov, M.F. Stel'makh, I.M. Ternov (+2 others)
1978 Uspehi fiziceskih nauk  
doi:10.3367/ufnr.0124.197802h.0355 fatcat:kojqteujkjh2xnytqjlshifkqq

QUASIOPTICAL SOLID-STATE GENERATOR WITH OPEN QUASI-FREQUENCY SPHEREOSELETAL OSCILLATING SYSTEM

Ivan Olkhovskiy, Anatoliy Fursov
2021 Bulletin of the National Technical University «KhPI» Series New solutions in modern technologies  
The results of research related to the development of an effective high-Q open oscillatory system of quasi-optical solid-state generators of millimeter and submillimeter wavelength ranges are presented. It is shown that for the stable operation of solid-state generators based on Gunn diodes and avalanche-transit diodes (ATDs) located inside an open resonator (OR), a significant rarefaction of the resonance frequency spectrum is required, which excludes jumps of the generation frequency. Taking
more » ... his requirement into account, a spheroechelett open resonator (SE OR) is proposed as an open oscillatory system of solid-state generators, one of the mirrors of which is a reflective lattice of the "echelette" type. The paper presents the results of "cold" measurements of the spectrum of resonance frequencies of the SE OP, which indicate that the SE OP indeed has a significantly rarefied spectrum both in transverse and, which is very important, in longitudinal modes of oscillations. The conditions necessary for the excitation of high-quality stable oscillations with high energy efficiency in a solid-state generator based on an SE OR are discussed and implemented. The results of an experimental study of a quasi-optical generator based on an 8-mm ATD wavelength range are presented. The analysis of the obtained characteristics and their qualitative explanation on the basis of the proposed model of the processes occurring in the investigated generator are presented. It is shown that the SE OR can be used as a resonant system in the entire EHF range of not only solid-state, but also electronic-vacuum devices. Finally, a way is outlined in the direction of further rarefaction of the spectrum of the SE OR in order to create a really single-frequency open oscillatory system.
doi:10.20998/2413-4295.2021.02.05 fatcat:aqiufurktjbrpfgxzj452fsoie

Solid-state generator of EHF range with increased long-term frequency stability

Ivan Olkhovskiy, Anatoly Fisun, Anatoliy Fursov
2019 Bulletin of the National Technical University «KhPI» Series New solutions in modern technologies  
Ivan Olkhovskiy -lecturer, Kharkiv College of State University of Telecommunications; Kharkiv, Ukraine; e-mail: olkhovskiy_i_p@ukr.net.  ...  Anatoliy Fursov -PhD, lecturer, Kharkiv patent-computer college; Kharkiv, Ukraine; e-mail: olkhovskiy_i_p@ukr.net.  ... 
doi:10.20998/2413-4295.2019.02.06 fatcat:lx5yqmqvvnganh274dmdyyb7le

Gradient-based adversarial attacks on categorical sequence models via traversing an embedded world [article]

Ivan Fursov, Alexey Zaytsev, Nikita Kluchnikov, Andrey Kravchenko, Evgeny Burnaev
2020 arXiv   pre-print
Deep learning models suffer from a phenomenon called adversarial attacks: we can apply minor changes to the model input to fool a classifier for a particular example. The literature mostly considers adversarial attacks on models with images and other structured inputs. However, the adversarial attacks for categorical sequences can also be harmful. Successful attacks for inputs in the form of categorical sequences should address the following challenges: (1) non-differentiability of the target
more » ... nction, (2) constraints on transformations of initial sequences, and (3) diversity of possible problems. We handle these challenges using two black-box adversarial attacks. The first approach adopts a Monte-Carlo method and allows usage in any scenario, the second approach uses a continuous relaxation of models and target metrics, and thus allows usage of state-of-the-art methods for adversarial attacks with little additional effort. Results for money transactions, medical fraud, and NLP datasets suggest that proposed methods generate reasonable adversarial sequences that are close to original ones but fool machine learning models.
arXiv:2003.04173v3 fatcat:4zds5zbxzzaqthax5f7quvaazi

Early Response of Antimicrobial Resistance and Virulence Genes Expression in Classical, Hypervirulent, and Hybrid hvKp-MDR Klebsiella pneumoniae on Antimicrobial Stress

Anastasiia D. Fursova, Mikhail V. Fursov, Evgenii I. Astashkin, Tatiana S. Novikova, Galina N. Fedyukina, Angelina A. Kislichkina, Irina A. Alexandrova, Olga N. Ershova, Ivan A. Dyatlov, Nadezhda K. Fursova
2021 Antibiotics  
Klebsiella pneumoniae is an increasingly important hospital pathogen. Classical K. pneumoniae (cKp) and hypervirulent K. pneumoniae (hvKp) are two distinct evolutionary genetic lines. The recently ongoing evolution of K. pneumoniae resulted in the generation of hybrid hvKP-MDR strains. K. pneumoniae distinct isolates (n = 70) belonged to 20 sequence types with the prevalence of ST395 (27.1%), ST23 (18.6%), ST147 (15.7%), and ST86 (7.1%), and 17 capsular types with the predominance of K2
more » ... K57 (18.6%), K64 (10.0%), K1 (5.7%) were isolated from patients of the Moscow neurosurgery ICU in 2014–2019. The rate of multi-drug resistant (MDR) and carbapenem-resistant phenotypes were 84.3% and 45.7%, respectively. Whole-genome sequencing of five selected strains belonging to cKp (ST395K47 and ST147K64), hvKp (ST86K2), and hvKp-MDR (ST23K1 and ST23K57) revealed blaSHV, blaTEM, blaCTX, blaOXA-48, and blaNDM beta-lactamase genes; acr, oqx, kpn, kde, and kex efflux genes; and K. pneumoniae virulence genes. Selective pressure of 100 mg/L ampicillin or 10 mg/L ceftriaxone induced changes of expression levels for named genes in the strains belonging to cKp, hvKp, and hybrid hvKp-MDR. Obtained results seem to be important for epidemiologists and clinicians for enhancing knowledge about hospital pathogens.
doi:10.3390/antibiotics11010007 pmid:35052884 pmcid:PMC8773033 fatcat:fiugbeylxna37gf4cuc7vczzii

Genotyping, Assessment of Virulence and Antibacterial Resistance of the Rostov Strain of Mycobacterium tuberculosis Attributed to the Central Asia Outbreak Clade

Mikhail V. Fursov, Egor A. Shitikov, Julia A. Bespyatykh, Alexander G. Bogun, Angelina A. Kislichkina, Tatiana I. Kombarova, Tatiana I. Rudnitskaya, Natalia S. Grishenko, Elena A. Ganina, Lubov V. Domotenko, Nadezhda K. Fursova, Vasiliy D. Potapov (+1 others)
2020 Pathogens  
The Central Asia Outbreak (CAO) clade is a growing public health problem for Central Asian countries. Members of the clade belong to the narrow branch of the Mycobacterium tuberculosis Beijing genotype and are characterized by multidrug resistance and increased transmissibility. The Rostov strain of M. tuberculosis isolated in Russia and attributed to the CAO clade based on PCR-assay and whole genome sequencing and the laboratory strain H37Rv were selected to evaluate the virulence on C57Bl/6
more » ... ce models by intravenous injection. All mice infected with the Rostov strain succumbed to death within a 48-day period, while more than half of the mice infected by the H37Rv strain survived within a 90-day period. Mice weight analysis revealed irreversible and severe depletion of animals infected with the Rostov strain compared to H37Rv. The histological investigation of lung and liver tissues of mice on the 30th day after injection of mycobacterial bacilli showed that the pattern of pathological changes generated by two strains were different. Moreover, bacterial load in the liver and lungs was higher for the Rostov strain infection. In conclusion, our data demonstrate that the drug-resistant Rostov strain exhibits a highly virulent phenotype which can be partly explained by the CAO-specific mutations.
doi:10.3390/pathogens9050335 pmid:32365818 fatcat:agocbyy6kngrtbmapbuodsine4

MDR and Pre-XDR Clinical Mycobacterium tuberculosis Beijing Strains: Assessment of Virulence and Host Cytokine Response in Mice Infectious Model

Mikhail V. Fursov, Egor A. Shitikov, Denis A. Lagutkin, Anastasiia D. Fursova, Elena A. Ganina, Tatiana I. Kombarova, Natalia S. Grishenko, Tatiana I. Rudnitskaya, Dmitry A. Bespiatykh, Nadezhda V. Kolupaeva, Viktoria V. Firstova, Lubov V. Domotenko (+7 others)
2021 Microorganisms  
Mycobacterium tuberculosis Beijing genotype associated with drug resistance is a growing public health problem worldwide. The aim of this study was the assessment of virulence for C57BL/6 mice after infection by clinical M. tuberculosis strains 267/47 and 120/26, which belong to the modern sublineages B0/W148 and Central Asia outbreak of the Beijing genotype, respectively. The sublineages were identified by the analysis of the strains' whole-genomes. The strains 267/47 and 120/26 were
more » ... zed as agents of pre-extensively drug-resistant (pre-XDR) and multidrug-resistant (MDR) tuberculosis, respectively. Both clinical strains were slow-growing in 7H9 broth compared to the M. tuberculosis H37Rv strain. The survival rates of C57BL/6 mice infected by 267/47, 120/26, and H37Rv on the 150th day postinfection were 10%, 40%, and 70%, respectively. Mycobacterial load in the lungs, spleen, and liver was higher and histopathological changes were more expressed for mice infected by the 267/47 strain compared to those infected by the 120/26 and H37Rv strains. The cytokine response in the lungs of C57BL/6 mice after infection with the 267/47, 120/26, and H37Rv strains was different. Notably, proinflammatory cytokine genes Il-1α, Il-6, Il-7, and Il-17, as well as anti-inflammatory genes Il-6 and Il-13, were downregulated after an infection caused by the 267/47 strain compared to those after infection with the H37Rv strain.
doi:10.3390/microorganisms9081792 pmid:34442871 pmcid:PMC8400193 fatcat:kbqovwp4bndafchzshpxhhpgt4

On Complexity of Searching a Subset of Vectors with Shortest Average Under a Cardinality Restriction [chapter]

Anton V. Eremeev, Alexander V. Kel'manov, Artem V. Pyatkin
2017 Communications in Computer and Information Science  
A Project Teams Creation based on Communities Detection 16:10 Alina Kadyrova and Konstantin Fursov Evolution of advanced technology studies: a search for communication core 16:20  ...  Networking Site Profiles 16:00 Mikhail Semenov, Elena Koroleva, Dilmurat Tursunov, Lev Bulygin A Project Teams Creation based on Communities Detection 16:10 Alina Kadyrova and Konstantin Fursov  ...  Bolsunovskaya The 360° Around View System for Large Vehicles, the Methods of Calibration and Removal of Barrel Distortion for Omnidirectional Cameras 11:20 Anton Korsakov, Ivan Fomin, Dmitry  ... 
doi:10.1007/978-3-319-52920-2_5 fatcat:tbsy74foabfybosqzxmdwxryee

Opriçnina Teşkilatı ve Rus Merkezileşmesine Etkileri

Tuğrul ÇAMAŞ
2018 VAKANÜVİS - ULUSLARARASI TARİH ARAŞTIRMALARI DERGİSİ  
Rus Devleti, XVI. yy da yaşadığı dönüşüm ve geçiş sürecine bağlı olarak iç ve dış politikada tüm tehditlere karşı İvan Groznıy kimliğinin izlerini taşıyan bir teşkilatlanma oluşturmuştur.  ...  Andrey Fursov bu yaklaşımın Altınordu fetih politikalarında uyguladığı toprak sistemi ile aynı olduğunu belirtmektedir. Bknz: Fursov, a.g.m. s. 150. 60 Froyanov, a.g.e., s.5 61 İ. A.  ...  A.L Yurganov, V.A Şarov, D.N Alışin, Y.V Anhimuk ve Andrey Fursov gibi Rus araştırmacılar Opriçnina hakkında önemli çalışmalar yapmışlardır.  ... 
doaj:2280f926ed934afebf4b4cb3603c3b59 fatcat:g5aj7pxwdzc2rhgno2zcprn2n4
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