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Modern methods of image recognition are sensitive to various types of disturbances, which actualize the development of resilient intelligent algorithms for safety-critical applications. The current article develops a model and method of training a classifier that exhibits characteristics of resilience to adversarial attacks, fault injection, and concept drift. The proposed model has a hierarchical structure of prototypes and hyperspherical boundaries of classes formed in the space of high-level features. Class boundaries are optimized during training and provide perturbation absorption and graceful degradation. The proposed learning method involves the use of a combined loss function, which allows the use of both labeled and unlabeled data, implements the compression of the feature representation to a discrete form and ensures the compactness of the distribution of classes and the maximization of the buffer zone between classes. The main component of the loss function is the value of the normalized modification of Shannon's information measure, averaged over the alphabet of the classes, expressed as a function of accuracy characteristics. Simultaneously, accuracy characteristics are calculated on the basis of smoothed versions of the distribution of statistical hypothesis testing results. It is experimentally confirmed that the proposed approach provides a certain level of disturbance absorption, graceful degradation and recovery. During testing of the proposed algorithm on the Cifar10 data set, it was established that the integral metric of resilience to tensor damage by inversion of one randomly selected bit is about 0.95 if the share of damaged tensors does not exceed 30%. Also, during testing of the proposed algorithm, it was established that an adversarial attack with a disturbance that does not exceed the L∞-norm threshold equal to 3 provides resilience that exceeds the value of 0.95 according to the integral metric. Additionally, the integral metric of resilience during adaptation to the appearance of two new classes is 0.959. The integral metric of resilience to the real drift of concepts between the two classes is 0.973. The ability to adapt to the appearance of new classes or the concept drift has been confirmed 8 times faster than learning from scratch.

An excess γ-ray signal toward the outer halo of M31 has recently been reported. Although other explanations are plausible, the possibility that it arises from dark matter (DM) is valid. In this work we interpret the excess in the framework of DM annihilation, using as our representative case WIMP DM annihilating to bottom quarks, and we perform a detailed study of the systematic uncertainty in the J-factor for the M31 field. We find that the signal favors a DM particle with a mass of ~45-72 GeV. While the mass is well constrained, the systematic uncertainty in the cross section spans 3 orders of magnitude, ranging from ~5 × 10-27-5 × 10-24 cm3 s-1. This high uncertainty is due to two main factors, namely, an uncertainty in the substructure nature and geometry of the DM halos for both M31 and the Milky Way (MW), and correspondingly, an uncertainty in the contribution to the signal from the MW's DM halo along the line of sight. However, under the conditions that the minimum subhalo mass is ≲10-6M⊙ and the actual contribution from the MW's DM halo along the line of sight is at least ~30% of its total value, we show that there is a large overlap with the DM interpretations of both the Galactic center (GC) excess and the antiproton excess, while also being compatible with the limits for the MW dwarf spheroidals. More generally, we summarize the results from numerous complementary DM searches in the energy range 10 GeV-300 GeV corresponding to the GC excess and identify a region in parameter space that still remains viable for discovery of the DM particle.

Purpose of this study is to investigate the problem of how typical (or, conversely, unique) is the phenomenon of explosive synchronization in networks of nonlinear oscillators with topologies of links such as “ring” and “small world”, and, in turn, how the partial frequencies of the interacting oscillators must correlate with each other for the phenomenon of explosive synchronization in these networks can be possible. Methods. In this paper, we use an analytical description of the synchronous behavior of networks of nonlinear elements with “ring” and “small world” link topologies. To confirm the obtained results the numerical simulation is used. Results. It is shown that in networks of nonlinear oscillators with topologies of links such as “ring” and “small world”, the phenomenon of explosive synchronization can be observed for the different distributions of partial frequencies of network oscillators. Conclusion. The paper considers an analytical description of the behavior of network oscillators with “ring” and “small world” topologies of links and shows that the phenomenon of explosive synchronization in such networks is atypical, but not unique.

Knowledge of fundamental properties of lead halide perovskites is crucial for their technological development. Here, authors perform magneto-optical spectroscopy, develop universal scaling laws and offer a predictive picture for interaction energies within photo-generated charge-carrier complexes.

Sustainable development requires implementation of relevant green transformation of countries by providing green policies and extending green technologies and renewable energies. Withal, it requires attracting additional knowledge, human, financial, and natural resources. In this case, countries with higher investment attractiveness have a higher capability to attract additional knowledge and resources to implement mechanisms and policies to achieve sustainable development goals. The effectiveness of public governance is a basic condition for the successful modernization of the economy to develop a positive business climate and attract investment. The paper aims at analysing the impact of institutions’ quality on a country’s investment attractiveness. The objects of research are Ukraine and the EU countries. The study applies correlation and regression analysis to achieve the purpose of the research. The findings show that institutions’ quality has a positive and statistically significant effect on a country’s investment attractiveness in the EU countries. However, in political stability, freedom and quality of governance positively influence a country’s investment attractiveness. Improving political stability by one point promotes the integrated index of a country’s investment attractiveness for the EU country by 0.086 and for Ukraine by 0.016. The impact of the rule of law on a country’s investment attractiveness is not statistically significant. This means that Ukraine has not formed an appropriate and affordable legislation base for attracting investors to the country. Thus, the Ukrainian government should pay attention to legislation for the regulation of social and economic development and energy and resource use.

Мета. Метою цієї роботи є висвітлення результатів економічного оцінювання наслідків забруднення ґрунтів важкими металами (на прикладі рухомих форм свинцю та кадмію) в системі сталого управління землями в аграрному секторі України. Методологія / методика / підхід. У дослідженні використано такі методи: бібліометричний, кластерний, графічний (для визначення стану досліджень щодо забруднення ґрунтів у світі на основі бази Scopus і наочного представлення результатів); групування (для визначення впливу показників за часткою забруднення площі с.-г. угідь рухомими формами свинцю та кадмію на ефективність використання земель); економетричне моделювання (для побудови стохастичних моделей впливу забруднення ґрунтів важкими металами на нормативну грошову оцінку ріллі й ефективність використання земель (в оцінці за виробництвом валової продукції сільського господарства, у тому числі рослинництва на 1 га с.-г. угідь) у розрізі областей України); монографічний та абстрактно-логічний (для узагальнення результатів дослідження). Інформаційною основою є дані про забруднення ґрунтів на землях сільгосппризначення в розрізі областей України за результатами Х туру агрохімічного обстеження земель і дані Державної служби статистики України. Дані щодо публікаційної активності оброблено з використанням програми «VOSviewer», побудову й статистичну оцінку економетричних моделей здійснено за допомогою програми STATISTICA і мови програмування R. Результати. Здійснено економетричне моделювання економічних резервів та оцінку наслідків (збитків) від забруднення ґрунтів важкими металами (на прикладі рухомих форм свинцю і кадмію) в регіонах України, що дало змогу розробити 14 стохастичних моделей. Установлено, що зменшення до прийнятних норм забрудненості свинцем ґрунтів України дозволить підвищити нормативну грошову оцінку ріллі на 3,2 % від середнього рівня, а резерв збільшення валової продукції сільського господарства та рослинництва в постійних цінах 2016 р. з розрахунку на 1 га с.-г. угідь відповідно становить 23,4 і 20,9 %. У разі подолання забрудненості кадмієм очікуване збільшення нормативної грошової оцінки ріллі становить 5,7 %, а резерв валової продукції сільського господарства та рослинництва з розрахунку на 1 га с.-г. угідь – відповідно 27,6 і 21,2 %. Оригінальність / наукова новизна. Уперше розроблено економетричні моделі, що дозволило здійснити кількісну оцінку впливу забруднення ґрунтів рухомими формами свинцю та кадмію на формування ефективності використання земель і нормативну грошову оцінку ріллі. Набули дальшого розвитку положення про формування системи сталого управління землями в аграрному секторі з урахуванням результатів економічного оцінювання наслідків забруднення ґрунтів. Це дослідження заповнює прогалини, виявлені в результаті бібліометричного й кластерного аналізу, а також сприяє кращому розумінню економічних резервів сталого управління землями в аграрному секторі України. Практична цінність / значущість. Ключові результати дослідження можуть бути використані для (і) вдосконалення ґрунтоохоронної політики держави в частині сталого управління забрудненими ґрунтами в аграрному секторі; (іі) оцінювання та прогнозування впливу забруднення ґрунтів важкими металами на ефективність використання земель на регіональному рівні; (iii) оцінювання ефективності ремедіації забруднених важкими металами ґрунтів на макрорівні з урахуванням запобігання/мінімізації можливих збитків.

Мета роботи: прогнозування показника ВВП та воєнних витрат України на довгострокову перспективу за різних сценаріїв розвитку війни та обсягів міжнародної фінансової допомоги. Метод дослідження: основними методами досліджень є експертні методи, метод статистичного аналізу, метод регресійного та кореляційного аналізу, методи математичної статистики, методи прогнозування. Результати дослідження: оцінки динаміки ВВП та воєнних витрат України на довгострокову перспективу за різних сценаріїв розвитку війни та обсягів міжнародної фінансової допомоги, а також оцінки приросту цих показників у абсолютних величинах та відсотках. Теоретична цінність дослідження: основною теоретичною цінністю статті є підхід до прогнозування показників ВВП та воєнних витрат України із урахуванням аналогії динаміки цих показників за досвідом попередній війн. Тип статті: теоретичний та практичний.

Purpose: review of domestic and foreign studies in the field of Internet addiction. Materials and methods. A review of the literature is presented and scientific studies on the prevalence of Internet addiction according to researchers from various countries are analyzed. The authors conducted a scientific search using the relevant keywords in the PubMed and Google Scholar search engines, in the Scopus, Web of Science, MedLine, The Cochrane Library, EMBASE, Global Health, CyberLeninka, RSCI (eLIBRARY.RU) and others databases. Results. Internet addiction is widespread among children, adolescents and adolescents, and every year their number is increasing. In most of the studies conducted to identify internet addiction, the most accessible research methods were used – questionnaires, questionnaires. Individuals of early adolescence who are prone to Internet addiction have anxiety-depressive states, difficulties in doing work, and high excitability. Conclusion. The results of studies of Internet addiction conducted in different countries of the world prove that this phenomenon has a worldwide prevalence and currently there are questions about the nosological affiliation, diagnostic criteria, clinical manifestations, and especially the prevention of Internet addiction.

During the COVID-19 pandemic number of patients suffering from symptoms, decreased work ability and the deterioration in quality of life for several weeks and even months after the onset of the disease is increasing. The aim of the literature review is to search and study the existing literature data regarding the lung impairment features in COVID-19, as well as the morphological and pathophysiological prerequisites for the long-term respiratory disorders in patients who have had this disease. The most common complaints of patients after acute COVID-19 are fatigue, dyspnea, cough and chest discomfort. In these cases restrictive pattern in the pulmonary function test, a reduced gas transfer and persistent changes in computed tomography often in the form of fibrosis are observed, less often in the form of bullous-emphysematous changes, bronchiectasis and pleural effusion. The main pathophysiological mechanisms of acute lung impairment in COVID-19 are direct viral toxicity, impaired function of the immune system, hyperinflammatory response, endotheliopathy, microcirculatory disorders and increased blood clotting with small and large vessels thrombosis, which can lead to pneumonia or acute respiratory distress syndrome. After the acute phase of COVID-19 the pathology of the lung can be caused by an immunogenic and hyperinflammatory response, hypercoagulability and lead to pulmonary fibrosis. The possible mechanisms of the pulmonary fibrosis are thrombotic processes, hemosiderosis, necrotic capillaritis, angiogenesis, hypoxia, cytokine storm. Thus abnormal immune response, hyperinflammation, endothelial dysfunction and excessive coagulation not only cause pneumonia or acute respiratory distress syndrome in acute COVID-19, but also may persist for a long time and contribute to pulmonary fibrosis in some patients. The causes of a longer duration and increased severity of the lung impairment in some people compared to others are the subject of current investigations.

Дані дослідження присвячені аналізу і вибору нейронних мереж різної архітектури та гібридних моделей, до яких включені нейронні мережі, для прогнозування ринкової вартості акцій на фондовому ринку країни, яка перебуває у процесі нестабільного розвитку. Аналіз та прогнозування таких фондових ринків не може бути проведено з використанням класичних методів. Актуальність теми дослідження зумовлена необхідністю розробки програмних систем, які реалізують алгоритмічне забезпечення прогнозування ринкової вартості акцій в Україні. Впровадження таких програмних систем до контуру прийняття інвестиційних рішень у компаніях, які зацікавлені у підвищенні інформаційної прозорості фондового ринку України, дасть можливість покращити прогнози щодо ринкової вартості акцій. Це у свою чергу сприятиме покращенню інвестиційного клімату та забезпечить зростання інвестування в українську економіку. Проведено аналіз результатів існуючих досліджень щодо використання нейронних мереж та інших методів обчислювального інтелекту для моделювання поведінки учасників фондового ринку та прогнозування ринку. У статті надано результати дослідження щодо використання нейронних мереж різної архітектури для прогнозування ринкової вартості акцій на фондових ринках України. Для прогнозування було обрано чотири акції Української фондової біржі: Центренерго (CEEN); Укртелеком (UTLM); Крюківський Вагонобудівний Завод ПАТ (KVBZ); Райффайзен Банк Аваль (BAVL). Для експериментального дослідження були обрані такі моделі: довга короткострокова пам’ять LSTM; згорткова нейронна мережа CNN; гібридна модель, яка поєднує дві нейронної мережі CNN і LSTM; гібридна модель, що складається з алгоритму декомпозиції варіаційного режиму та нейронної мережі довгострокової пам’яті (VMD-LSTM); гібридна модель VMD-CNN-LSTM глибокого навчання на основі варіаційного режиму (VMD) та двох нейронних мереж. Розраховано оцінки якості прогнозу за різними метриками. Зроблено висновок, що використання гібридної моделі VMD-CNN-LSTM дає мінімальну помилку прогнозування ринкової вартості акцій українських підприємств. Також доцільно використовувати модель VMD-LSTM для прогнозування на біржах країн з нестабільною економікою.

Diffractograms of rotated polyaniline fiber grating were studied experimentally. Based on the obtained results, the diffraction patterns were analyzed and set of experimental data obtained after image digitization was approximated by the least squares method. The angle of rotation of the diffraction grating was calculated using the determined coefficients of the second-order curves.

This article is about how crowdfunding and crowdinvesting systems can be used during crises and hostilities. This article provides examples of different types of possible crowd-system. Research subject. Crowdfunding and crowdinvesting systems as the institutional instruments (P2P) which are used during crises and hostilities, among them are as follows: Violence Crowdfunding systems, General Crowdfunding Systems, and Crowdinvesting Systems alike. Methodology. The authors used a complex of research methods and approached as interdisciplinary approach, evidence-based approach, and practical business cases. Also, general scientific research methods were used (analysis and synthesis of information), as well as an inductive and deductive research methods. The goal of the article is to consider the prospects for the use of crowdfunding platforms as an element of solving the military crisis on the territory of Ukraine. Conclusions. The Special attention was paid to the war crises in Ukraine and the situation of the crowdfunding and crowdinvesting systems in Ukrainian society. It is provided detailed examples of the use of crowdsourcing systems in Ukraine during the war nowadays and explained the need for the creation of an independent Ukrainian crowdfunding platform. Additionally, the ways of the creation of such a platform are clarified. Ukrainian society during the military crisis gained experience in crowdfunding that was not familiar or even available. However, Ukrainian society is very actively popularizing crowdfunding or rather its foundations. Crowdfunding is currently most common when looking for funding for military needs: from mass arms purchases to financing individual soldiers. In a short time, thanks to the stress of war, many people have made crowdfunding a part of their lives and instilled this habit in society. The first crowdfunding platforms are already appearing to give Ukrainians the opportunity to fund some Ukrainian startups, companies, and ideas. One of the most difficult elements in creating and launching a crowdfunding platform is not building the platform itself, but integrating it. A decade ago, the creation of a crowdfunding platform and integration of the entire crowdfunding system, was a complicated and costly procedure. The most difficult thing is to integrate the platform into society so that mass use can begin.

The article identifies the problems and prospects for improving the management of the development of insurance companies in Ukraine. The need to make strategically effective decisions that maximize the adaptation of insurance companies to the external environment, the formation of tactical tasks on their basis, is detected. It is noted that, like any economic activity, insurance requires the introduction of a quality management system. Hence, the overall efficiency of insurance company management consists of the levels of efficiency of managing individual subsystems: financial resources, marketing, sales, etc. In the existing structural and process model of an insurance company, the boundaries between structural levels are not clearly defined. Some elements of structures equally belong to different structural groups, in which case often one structure overlaps or intersects with another. It is found that government regulation of insurance companies should be based on principles that will ensure its efficiency, adequacy and transparency, promote the development and profitability of insurance providers and protect consumers of insurance services. It is concluded that one of the important conditions for effective management of the development of insurance companies in Ukraine is the use of modern management technologies and government support in the form of regulation of their activities, based on certain principles that ensure its efficiency, adequacy and transparency, will contribute to the development and profitability of insurance workers and protect consumers of insurance services. A methodical approach to determining the efficiency of managing the development of insurance companies is proposed, which is based on the use of the following coefficients: uncertainty of management activities; concentration of functions; accumulation of dysfunctions by the organizational structure; rationalization of the use of elements; concentration of elements; complexity of the organizational structure of management, which allows to establish the differences between the existing and the desired state of the basic indicators of the efficiency of the development management system of an economic entity

Aim of this work is to study the possibility of existence of multistability near the boundary of generalized synchronization in systems with complex attractor topology. Unidirectionally coupled Lorentz systems have been chosen as an object of study, and a modified auxiliary system method has been used to detect the presence of the synchronous regime. Result of the work is a proof of the presence of multistability near the boundary of generalized synchronization in unidirectionally coupled systems with a complex topology of attractor. For this purpose, the basins of attraction of the synchronous and asynchronous states of interacting Lorenz systems have been obtained for the value of the coupling parameter corresponding to the realization of the intermittent generalized synchronization regime in the system under study, and the dependence of the multistability measure on the value of the coupling parameter has also been calculated. It is shown that in the regime of intermittent generalized synchronization the measure of multistability turns out to be positive, which is an additional confirmation of the presence of multistability in this case.

The purpose of the study. To assess the levels of situational and personal anxiety in patients with chronic obstructive pulmonary disease (COPD) in conditions of comorbidity with arterial hypertension (AH). Materials and methods. The study included 92 male patients with COPD. Of these, 63 patients with COPD in combination with hypertension. The diagnosis of COPD verified and the severity assessed in accordance with the GOLD criteria. The Spielberger-Hanin scale used to assess the level of situational and personal anxiety. Results. It s found that men with COPD in conditions of comorbidity with hypertension are characterized by statistically significantly higher values of the average score of both situational and personal anxiety on the Spielberger-Hanin scale. In this group of examined patients, patients with indicators of situational and personal anxiety corresponding to a high level and less often to a low level of anxiety were significantly more common. Among men with COPD of the IV st., persons with high levels of situational and personal anxiety were significantly more common. Conclusion. The results of the study demonstrated a high level of anxiety disorders in COPD patients, especially in people with comorbidity with hypertension and a positive relationship between the level of anxiety and the severity of the disease.

Abstract Superconducting fluxonium qubits provide a promising alternative to transmons on the path toward large-scale superconductor-based quantum computing due to their better coherence and larger anharmonicity. A major challenge for multi-qubit fluxonium devices is the experimental demonstration of a scalable crosstalk-free multi-qubit architecture with high-fidelity single-qubit and two-qubit gates, single-shot readout, and state initialization. Here, we present a two-qubit fluxonium-based quantum processor with a tunable coupler element. We experimentally demonstrate fSim-type and controlled-Z-gates with 99.55 and 99.23% fidelities, respectively. The residual ZZ interaction is suppressed down to the few kHz levels. Using a galvanically coupled flux control line, we implement high-fidelity single-qubit gates and ground state initialization with a single arbitrary waveform generator channel per qubit.

The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray species to understand cosmic-ray production and propagation in the Galaxy. For instance, low-energy antideuterons would provide a "smoking gun" signature of dark matter annihilation or decay, essentially free of astrophysical background. Studies in recent years have emphasized that models for cosmic-ray antideuterons must be considered together with the abundant cosmic antiprotons and any potential observation of antihelium. Therefore, a second dedicated Antideuteron Workshop was organized at UCLA in March 2019, bringing together a community of theorists and experimentalists to review the status of current observations of cosmic-ray antinuclei, the theoretical work towards understanding these signatures, and the potential of upcoming measurements to illuminate ongoing controversies. This review aims to synthesize this recent work and present implications for the upcoming decade of antinuclei observations and searches. This includes discussion of a possible dark matter signature in the AMS-02 antiproton spectrum, the most recent limits from BESS Polar-II on the cosmic antideuteron flux, and reports of candidate antihelium events by AMS-02; recent collider and cosmic-ray measurements relevant for antinuclei production models; the state of cosmic-ray transport models in light of AMS-02 and Voyager data; and the prospects for upcoming experiments, such as GAPS. This provides a roadmap for progress on cosmic antinuclei signatures of dark matter in the coming years.

We study the generation of entanglement between two qubits which communicate through a single cavity mode of quantum light but have no direct interaction. We show that such entanglement can be generated simply by exchanging quanta with a third party, which is in our case the cavity mode. Exchanging only a single quantum creates maximal entanglement. A single quantum can be provided by an external quantum light source. However, we use a classical light source to pump quanta which are used for the exchange, and investigate the degree of two-qubit entanglement. We first identify a characteristic timescale of the interaction between the cavity mode and each qubit. We investigate two regimes of the driving pulse length: one is short and the other is long compared to the characteristic timescale of the interaction. In the first regime, it is known that the pulse can pump the system by generating a displacement of the cavity mode. We show that, by using a specific pulse shape, one can make the displacement essentially vanish after the pulse finishes interaction with the cavity mode. In this case, a rotation of the qubits can be invoked. In addition, higher-order effects of the pulse including a nonlocal operation on the joint system of the cavity mode and the qubits are found, and we present a formalism to compute each term up to a given order. An explicit condition on the pulse shape for each term to be nonzero or suppressed is derived to enable an experimental design for verifying the entanglement generation using a classical light source. In the opposite regime where the driving is sufficiently long, we utilize a squeezed state which may be obtained adiabatically. We study how the squeezing and the accompanied rotation of qubits affect the generated two-qubit entanglement.