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The paper presents the results of studying the parameters of the contact interaction between the tool indenter and the work surface of parts while machining by methods of surface plastic deformation by diamond smoothing and ball burnishing. Changes in the technological factors of diamond smoothing and burnishing under relatively equal machining conditions have different effects on the formation of the topography and parameters of the microprofile. This is due to the contact character of the indenter with the surface. When diamond smoothing, the indenter is rigidly fixed in the tool holder, whereas for ball burnishing the indenter rotates. Accordingly, sliding friction prevails for smoothing, and rolling friction prevails for burnishing. Friction forces in the contact area of the tool indenter with the surface of the part affect the processes. Friction coefficient depends on the deformation and adhesive components. The processes of plastic deformation of metal, the quality of the work surface and other machining parameters in the contact area of the indenter with the work surface are greatly influenced by the strength of the adhesive bond and the molecular component of the friction coefficient. The values of these factors are determined by the combination of materials of the contacting surfaces. This information is often not available in the reference and scientific sources, and theoretical calculations do not allow taking into account real machining factors. The paper presents the methodology and some results of studying the molecular component of the friction coefficient, the specific strength of the adhesive bond and the pressure coefficient in the contact area of the indenter with the surface during diamond smoothing and ball burnishing. The presented results give the scientific novelty of the paper.

In this paper, we demonstrate the laser characterization of Cr:ZnS/Se polycrystalline gain media in non-selective unpolarized, linearly polarized, and twisted mode cavities. Lasers were based on post-growth diffusion-doped, commercially available antireflective-coated Cr:ZnSe and Cr:ZnS polycrystals with a length of 9 mm. The spectral output of lasers based on these gain elements in non-selective unpolarized and linearly polarized cavities was measured to be broadened to ∼20-50 nm due to the spatial hole burning (SHB) effect. SHB alleviation in the same crystals was realized in the “twisted mode” cavity, with linewidth narrowing to ∼80-90 pm. Both broadened and narrow-line oscillations were captured by adjusting the orientation of intracavity waveplates with respect to facilitated polarization.

This paper is devoted to the problem of the best recovery of a fractional power of the B-elliptic operator of a function on R+N by its Fourier–Bessel transform known approximately on a convex set with the estimate of the difference between Fourier–Bessel transform of the function and its approximation in the metric L∞. The optimal recovery method has been found. This method does not use the Fourier–Bessel transform values beyond a ball centered at the origin.

It was demonstrated that in the nonselective cavities, suppression of the spatial hole burning via "mode twisting" for lasers based on polycrystalline Cr:ZnS and Cr:ZnSe results in linewidth narrowing to ~80-90 pm from ~20-50 nm.

The first vanadium selenoiodide V

The advent of chirped-pulse amplification in the 1980s and femtosecond Ti:sapphire lasers in the 1990s enabled transformative advances in intense laser–matter interaction physics. Whereas most of experiments have been conducted in the limited near-infrared range of 0.8–1 μm, theories predict that many physical phenomena such as high harmonic generation in gases favor long laser wavelengths in terms of extending the high-energy cutoff. Significant progress has been made in developing few-cycle, carrier-envelope phase-stabilized, high-peak-power lasers in the 1.6–2 μm range that has laid the foundation for attosecond X ray sources in the water window. Even longer wavelength lasers are becoming available that are suitable to study light filamentation, high harmonic generation, and laser–plasma interaction in the relativistic regime. Long-wavelength lasers are suitable for sub-bandgap strong-field excitation of a wide range of solid materials, including semiconductors. In the strong-field limit, bulk crystals also produce high-order harmonics. In this review, we first introduce several important wavelength scaling laws in strong-field physics, then describe recent breakthroughs in short- (1.4–3 μm), mid- (3–8 μm), and long-wave (8–15 μm) infrared laser technology, and finally provide examples of strong-field applications of these novel lasers. Some of the broadband ultrafast infrared lasers will have profound effects on medicine, environmental protection, and national defense, because their wavelengths cover the water absorption band, the molecular fingerprint region, as well as the atmospheric infrared transparent window.

10 µm lasing is studied in a compact CO

In this paper, a criterion for generating an analytic family of operators, which resolves a linear equation solved with respect to the Dzhrbashyan–Nersesyan fractional derivative, via a linear closed operator is obtained. The properties of the resolving families are investigated and applied to prove the existence of a unique solution for the corresponding initial value problem of the inhomogeneous equation with the Dzhrbashyan–Nersesyan fractional derivative. A solution is presented explicitly using resolving families of operators. A theorem on perturbations of operators from the found class of generators of resolving families is proved. The obtained results are used for a study of an initial-boundary value problem to a model of the viscoelastic Oldroyd fluid dynamics. Thus, the Dzhrbashyan–Nersesyan initial value problem is investigated in the essentially infinite-dimensional case. The use of the proved abstract results to study initial-boundary value problems for a system of partial differential equations is demonstrated.

We present recent results on 1645/1617 nm Er:YAG and 2090 nm Ho:YAG laser systems optically pumped by efficient CW fiber lasers. Multi-mJ pulse energy, MW-level peak powers are obtained in a range of repetition rates.

This study describes the development of information and technological support that accumulates information and analytical materials concerning the sanitary and epidemiological environments of the Russian Arctic population. Maintaining a healthy epidemiological situation is vital for the Arctic region. However, active development of the Arctic region is ongoing. The penetration of pathogens into the region is unacceptable.

This chapter encourages the discussion over ecclesiological and canonical problems between the Orthodox and the Eastern Catholics as a way not to escape the missiological perspective but, rather, focus on it. According to the Concept of the Revival of the Missionary Activity of the Russian Orthodox Church (ROC), reconciliation is one of the five directions of the mission. In the face of increasing secularization and globalization, collaboration in missionary projects can prove an efficient tool for reconciliation. Given the presence of a common threat, namely, fundamentalist enthusiasm in our churches, it makes sense to work together, learning from each other in order to overcome the temptation of fundamentalism.

We present spectroscopic characterization of the laser active LiF:F2+ and LiF:F2- crystals over 20 years period. We demonstrated laser oscillations in these crystals despite some degradation of the active centers.

We report on the highly efficient, octave-spanning mid-infrared (mid-IR) optical parametric amplification (OPA) in a ZnGeP(2) (ZGP) crystal, pumped by a 1 kHz, 2.4 μm, 250 fs Cr:ZnSe chirped-pulse amplifier. The full spectral coverage of 3−10 μm with the amplified signal and idler beams is demonstrated. The signal beam in the range of ∼3 − 5 μm is produced by either white light generation (WLG) in YAG or optical parametric generation (OPG) in ZGP using the common 2.4 μm pump laser. We demonstrate the pump to signal and idler combined conversion efficiency of 23% and the pulse energy of up to 130 μJ with ∼2 μJ OPG seeding, while we obtain the efficiency of 10% and the pulse energy of 55 μJ with ∼0.2 μJ WLG seeding. The OPA output energy is limited by the available pump pulse energy (0.55 mJ at ZGP crystal) and therefore further energy scaling is feasible with multi-stage OPA and higher pump pulse energy. The autocorrelation measurements based on random quasi-phase matching show that the signal pulse durations are ∼318 fs and ∼330 fs with WLG and OPG seeding, respectively. In addition, we show the spectrally filtered 30 μJ OPA output at 4.15 μm suitable for seeding a Fe:ZnSe amplifier. Our ultrabroadband femtosecond mid-IR source is attractive for various applications, such as strong-field interactions, dielectric laser electron acceleration, molecular spectroscopy, and medical surgery.

The article examines the issues of agricultural production by the agrarians of the Russian Federation in the context of import substitution and their contribution to the formation of food independence in the region. The dynamics of agricultural production in such sectors as crop and livestock production has been analyzed. In recent years, thanks to new innovative technologies in crop production, there has been a positive trend towards an increase in gross harvest, as well as an increase in crop yields. So, in particular, for more than thirty years of the analyzed period of time, gross agricultural production increased by 6110.4 billion rubles, and in the sectors crop and livestock production there was an increase in production by 3276.8 billion rubles. and by 2833.8 billion rubles. These indicators were influenced by such innovative developments in crop production as binary crops, new varieties of agricultural crops, as well as a significant increase in the use of fertilizers on agricultural land.

Timely detection of surface damages on wind turbine blades is imperative for minimizing downtime and avoiding possible catastrophic structural failures. With recent advances in drone technology, a large number of high-resolution images of wind turbines are routinely acquired and subsequently analyzed by experts to identify imminent damages. Automated analysis of these inspection images with the help of machine learning algorithms can reduce the inspection cost. In this work, we develop a deep learning-based automated damage suggestion system for subsequent analysis of drone inspection images. Experimental results demonstrate that the proposed approach can achieve almost human-level precision in terms of suggested damage location and types on wind turbine blades. We further demonstrate that for relatively small training sets, advanced data augmentation during deep learning training can better generalize the trained model, providing a significant gain in precision.

Timely detection of surface damages on wind turbine blades is imperative for minimising downtime and avoiding possible catastrophic structural failures. With recent advances in drone technology, a large number of high-resolution images of wind turbines are routinely acquired and subsequently analysed by experts to identify imminent damages. Automated analysis of these inspection images with the help of machine learning algorithms can reduce the inspection cost, thereby reducing the overall maintenance cost arising from the manual labour involved. In this work, we develop a deep learning based automated damage suggestion system for subsequent analysis of drone inspection images. Experimental results demonstrate that the proposed approach could achieve almost human level precision in terms of suggested damage location and types on wind turbine blades. We further demonstrate that for relatively small training sets advanced data augmentation during deep learning training can better generalise the trained model providing a significant gain in precision.

Impact fatigue caused by rain droplets, also called rain erosion, is a severe problem for wind turbine blades and aircraft. In this work, an assessment of impact fatigue on a glass fibre reinforced polymer laminate with a gelcoat is presented and the damage mechanisms are investigated. A single point impact fatigue tester is developed to generate impact fatigue damage and SN data. Rubber balls are repeatedly impacted on a single location of the coated laminate. Each impact induces transient stresses in the coated laminate. After repeated impacts, these stresses generate cracks, leading to the removal of the coating and damage to the laminate. High-resolution digital imaging is used to determine the incubation time until the onset of coating damage, and generate an SN curve. An acoustic emission sensor placed at the back of the laminate monitors changes in acoustic response as damage develops in the coated laminate. The subsurface cracks are studied and mapped by 3D X-ray computed tomography. A finite element method model of the impact shows the impact stresses in the coating and the laminate. The stresses seen in the model are compared to cracks found by 3D tomography. The damage is also evaluated by ultrasonic scanning.

In article influence of dynamic characteristics of instruments of elastic action on technological stability of processes of superficial plastic deformation at a diamond ironing of flat and cylindrical surfaces of details of machinery are considered.

Heterojoncțiunile CdS/Cd1-xMnxTe au fost obținute aplicând metoda de volum cvasiînchis. La studierea proprietă­ților electrice și fotoelectrice ale acestor structuri s-a constatat că fotosensibilitatea a crescut esențial datorită tratării termice în clorură de cadmiu, iar eficiența celulei solare (CS) este de 10,29%. Aceasta se datorează micșorării recombinării purtătorilor de sarcină la suprafață și particularităților proprietăților electrice și fotoelectrce ale acestor structuri.INFLUENCE OF THE Cd1-xMnxTe THICKNESS ON PHOTOVOLTAIC PARAMETERS OF THE CdS/Cd1-xMnxTe HETEROJUNCTIONHeterojunction CdS/Cd1-xMnxTe has been obtained by quasi-closed volume method. Photosensibility increases sharply due to the thermal treatment in the cadmium chloride analyzing electrical and photoelectrical properties of these structures. The solar cell efficiency is 10.29% and is caused by decreased recombination process and specific electrical and photoelectrical properties.

Background Welders are exposed to a number of metallic elements during work. Bioaccessability, that is important for element uptake, has been little studied. This study addresses bioaccessability and uptake of chromium (Cr), molybdenum (Mo), tungsten (W) and vanadium (V) among welders. Methods Bioaccessability of Cr, Mo, V and W was studied in airborne particulate matter collected by personal sampling of the workroom air among shipyard welders by using the lung lining fluid simulant Hatch solution. Associations between concentrations of Hatch soluble and non-soluble elements (Hatchsol and Hatchnon-sol) and concentrations of the four elements in whole blood, serum, blood cells and urine were studied. Results Air concentrations of the four elements were low. Only a small fraction of Cr, V and W was Hatchsol, while similar amounts of Mo were Hatchsol and Hatchnon-sol. Welders (N = 70) had statistically significantly higher concentrations of all four elements in urine and serum when compared to referents (N = 74). Highly statistically significant associations were observed between urinary W and Hatchsol W (p Conclusions Associations between Hatchsol elements in air and their biological concentrations were higher than when Hatchnon-sol concentrations were considered. Associations were generally higher when air samples collected the day before biological sampling were considered as compared to air samples collected two days before.

The document Together towards Fife: Mission and Evangelism in Changing Landscapes (TTL) is a timely and relevant milestone on the way of defining ecumenical strategies and tactics for the life of Christian communities in our rapidly changing and increasingly globalized world. It is of current interest especially for Russian missiology because, as a field of studies, missiology has taken shape only in the last twenty years. The pre-revolutionary history of Russian Orthodoxy knows several names of missionary devotees, and conceptualizing missionary activities began in the late 19th century, but this movement was cut short following the establishment of Bolshevik regime in 1917. The missiology that originated in the West in the 20th century has only recently been brought to study in Russia. More than half a century of membership of the Moscow Patriarchate in the World Council of Churches (WCC) has partially made up for the shortage of ecclesial and theological fellowship of churches from the ideologically opposing systems. Still, so far perceptions associated with ecumenism in mass consciousness of Russian believers (not only Orthodox) are vague and distorted. The first thing to note is the invaluable act of bringing the subject "mission and evangelism" to the attention of the 10th Assembly of the WCC. Hitherto, most of the believers, and even most of the clergy, remained unaware of the fact that ecumenism is simply co-working for the cause of Christian mission. Discussion of the topic, and that within the context of the recently celebrated centenary of the 1910 Edinburgh Conference, will deepen missionary consciousness both of Christian leaders and laity. Oddly enough, the need for Christian cooperation and unity that was felt unquestionable by many missionaries a century ago remains unobvious for some of our contemporaries. Another significant issue is "changing landscapes." Strategies and tactics of the mission should be determined by a current situation in the missionary field; that is, they should be a function of numerous factors--social, political, psychological, economic, cultural, linguistic, etc. The task of saving traditional values involves renewing the concepts and methods of the mission. It is hardly reasonable today to take mission as increasing membership of the community rather than missio Dei. (1) Yet regrettably, for Russian Orthodox believers there still remain some barriers. The idea of our faith as traditional, conservative, resistant to any influence that is implanted in the minds of the Orthodox believers makes their situation still more confused. It is often said that renewal, aggiornamento, is contraindicated to Orthodoxy. Yes, it is traditional, but it is a living Tradition. Yes, it is conservative, but in the sense that it serves preaching and conservation of the eternal values of the Gospel. The Church as a Theandric organism cannot but interact with the social milieu, cannot but look for a language to communicate those who are to listen to the Gospel. Missiological reasoning for such a position can start from the notion of "inculturation" introduced into missiology in the last quarter of the XXth century. Since horizontal, geographical inculturation is readily apparent, it seems natural to admit chronological inculturation as well. (2) Within the context of the concept of missio Dei, highly relevant is an emphasis on the Christian contribution to the mission with special reference to creation. The late 20th century highlighted implications and significance of the fact that theological contemplations on the economy of salvation, ecology, and economy stem from a common root: that is, oikos. Logic leads us from theology to ecology, from ecology to the ecumenical values of cooperation and responsibility for the creation and humankind that we all share. (3) The fact that the Basis of the Social Concept (in 2000) (4) contained a section on ecology and that in 2013 the Russian Orthodox Church had a specially developed document conceptualizing its position on ecological problems (5) is evidence of the particular interest the Russian Orthodox Church will have in the parts of TTL that deal with creation. …

С. 11-13. 2. Захаров, А.А. Пути совершенствования методики силовой подготовки спортс-менов в мас-рестлинге / А.А. Захаров, Я.Ю. Захарова // Ученые записки университета имени П.Ф. Лесгафта. – 2010. – № 11 (69). – С. 39-42. 3. Захаров, А. А. Методика силовой подготовки спортсменов-разрядников в мас-рестлинге / А.А. Захаров // Современные проблемы физической культуры и спорта : ма-териалы конференции. – Хабаровск, 2012. – С. 88-91. 4. Захаров, А. А. Методика развития локальной силовой выносливости хвата в мас-рестлинге / А.А. Захаров, В.В. Федоров // Современные проблемы физической куль-туры и спорта : материалы конференции. – Хабаровск, 2012. – С. 83-84. REFERENCES 1. Dmitriev, O.A., Ilyushchenko, D.A. and Fetisov, V.S. (2010), “Carpal dynamometer and software for evaluation of the physiological condition of the athlete”