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In today’s trade, the vast majority of commercial transactions in both domestic and international trade are concluded by applying trade credit terms. The aim of this article is to analyse the trade credit insurance and, according to the methodology, to evaluate it as a credit risk management tool in the context of Lithuanian business market. The authors have proposed a methodology that combines theoretical and practical research methods. First of all, with assistance of qualitative analysis, the alternative external credit risk management tools were examined. Such analysis allows not only to identify the advantages, disadvantages and benefits of researched risk management tools but also to assess the efficiency and rationality of trade credit insurance in the context of alternative methods. In order to carry out an assessment in the practical aspect, considering the lack of statistical data, it was decided additionally to perform an expert evaluation. After performing an assessment of trade credit insurance, it was concluded that in international trade, with a large buyer portfolio and high sales volume, the trade credit insurance becomes the most effective and rational way to manage credit risk, which eliminates the losses because of the debtor’s insolvency or bankruptcy, manages countries and sector’s risks and helps to discipline the debtor, what determines the decline in overdue accounts frequencies, amounts and volumes.

The influence of relaxation and rejuvenation on the deformation behavior of the Zr-based bulk metallic glass Vit105 (Zr52.5Cu17.9Ni14.6Al10Ti5) was investigated, where a well-defined thermal history was systematically introduced by thermal treatments. Samples with a progressively lower fictive temperature exhibit a lower enthalpic state, coupled with a reduced degree of free volume, which is responsible for a continuous embrittlement observed in three-point beam bending tests. The generated database allows an assessment of the mechanical behavior of any amorphous component made of Vit105 by simple calorimetric measurements and the determination of the fictive temperature, which is of special interest for complex parts that cannot be easily evaluated in mechanical tests. Diffraction experiments with high energy synchrotron X-ray radiation reveal a correlation between the increase in rigid 3-atom cluster connections with the reduction in the fracture strain, as a measure of ductility, indicating a strong correlation with the thermal history. While the atomic connections seem to have a crucial contribution to the ductility, changes of the short- and medium-range order seem to be equally important. The current findings provide fundamental insights into the role of thermal history in metallic glass forming alloy systems and how it can be used to manipulate the structure and tailor their mechanical properties specifically to the needs of each application.

Tropical sea surface temperature (SST) variability, mainly driven by the El Niño–Southern Oscillation (ENSO), influences the atmospheric circulation and hence the transport of heat and chemical species in both the troposphere and stratosphere. This paper uses Met Office, ERA5 and MERRA2 reanalysis data to examine the impact of SST variability on the dynamics of the polar stratosphere and ozone layer over the period from 1980 to 2020. Particular attention is paid to studying the differences in the influence of different types of ENSO (East Pacific (EP) and Central Pacific (CP)) for the El Niño and La Niña phases. It is shown that during the CP El Niño, the zonal wind weakens more strongly and changes direction more often than during the EP El Niño, and the CP El Niño leads to a more rapid decay of the polar vortex (PV), an increase in stratospheric air temperature and an increase in the concentration and total column ozone than during EP El Niño. For the CP La Niña, the PV is more stable, which often leads to a significant decrease in Arctic ozone. During EP La Niña, powerful sudden stratospheric warming events are often observed, which lead to the destruction of PV and an increase in column ozone.

During various marine container handling operations, performed mainly in larger-scale container terminals, containers get damaged regularly. Our previous studies showed that each physical impact results in some form of physical deformation of the backbone structure. Even at low accelerations, the spreaders of the quay cranes impact the containers with enough force to substantially bend the metal parts of the corners of the containers, when additional hooking procedures are required. This means that the first time resulted in the metal rods hitting the metal frame with an average 15-ton mass at the average speed of 1.7 m/s. The metal rods of the hooking mechanisms’ impact areas of the containers are structurally important, and each impact surely damages the containers, diminishing their total operational time. We have already proposed the Impacts Detection Methodology (IDM) and its application system, tested in Klaipeda City port, and it proved to be efficient in real-time operations, detecting concurrent impacts with each new handling cycle. In this paper, we provide a summarisation of a larger number of detections using the IDM, and as a result of this analysis, we have detected that more impact events happen when containers are taken from the upper parts of the ship, in comparison to the ones taken from the shafts. Results suggest that more critical events occur due to operator actions and experiences working with the machinery, yet the same operators tend to make fewer impact mistakes taking the containers from the shafts as the vertical cell guides tend to direct the movements and lower the levels of the natural sway of the spreader inside closed environments. This surely damages the metal infrastructure of the shafts, as seen in our previous study, but minimizes the chances of secondary impacts occurring during hooking.

This study aims to address the problem of proper shipping container damage detection during the hooking procedure performed by quay cranes and their hooking mechanisms. We adopted the Impacts Detection Methodology (IDM), developed previously, to detect repeated impacts on the same areas of the container. These concurrent impacts indicate false hooking procedures, which result in dangerous metal deformations in these areas over short periods of operational time. This application intends to verify if this methodology is adaptable in real-life applications to detect these specific events. Our main results indicate that more than half of handling procedures are carried out with a higher risk of structural damage to the containers due to these repeated impacts, which can reach up to five concurrent impacts in some case studies.

The Pamir and Hindu Kush are examples of a puzzling collision system where a complex junction of colliding lithospheric plates coexists with intermediate depth seismicity at 300 km. In this study, we constructed a new tomography model using travel time data from local events recorded by the TIPAGE (Tien Shan--Pamir Geodynamic program) network. In addition to the P- and S-wave velocities down to 200 km, we derived the azimuthal anisotropy. The velocity anomalies were consistent with the results of previous studies. In the crust, the velocity structure and anisotropy directions were mainly oriented along major suture zones. At depths of 80-120 km, a narrow low-velocity anomaly coinciding with the distribution of deep seismicity was interpreted as a trace of entrained crustal material by the dipping lithosphere. The anisotropy directions at these depths were mainly oriented northwest-southeast and were interpreted as indicating the direction of the motion of colliding plates. The difference in the magnitude of anisotropy south and north of the Pamir seismic zone suggests that the lithosphere coming from the south possesses less anisotropy than that of the Asian plate. The local tomography model was supplemented by previously computed regional tomography that expanded the area both laterally and axially. Beneath the Pamir, both continental plates coming from the north and south form a drop-shaped anomaly that will possibly delaminate in time. Beneath the Hindu Kush, we could clearly trace a continuous almost vertical subduction of the Katawaz block from the south. Thus, the continental collision beneath the Pamir and subduction beneath the Hindu Kush are separate processes with different rates and directions of plate movement. Key words: Pamir, Hindu Kush, seismic tomography, anisotropy, continental collision, subduction. Le Pamiretl'Hindu Kush sont des exemples d'un systeme enigmatiquedecollision dans lequel coexistent une jonction complexe de plaques lithospheriques convergentes et une sismicite de profondeur intermediaire, a 300 km. Nous avons construit un nouveau modele tomographique en utilisant des donnees de temps de trajets d'evenements locaux enregistres par le reseau TIPAGE (programme geodynamique Tien Shan-Pamir).En plusdevitesses des ondesP etSjusqu'a 200 kmde profondeur, nous avons determine l'anisotropie azimutale. Les anomalies de vitesse concordent avec les resultats d'etudes anterieures. Dans la croute, la structure de vitesses et les directions d'anisotropie sont principalement orientees parallelement a des zones de suture majeures. A des profondeurs de 80-120 km, une etroite anomalie de faible vitesse coincidant avec la repartition de la sismicite profonde est interpretee comme representant la trace de materiau crustal entraine par la lithosphere plongeante. Les directions d'anisotropie a ces profondeurs sont principalement nord-ouest-sud-est et indiqueraient la direction de deplacement de plaques convergentes. La difference de magnitude de l'anisotropie au sud et au nord de la zone sismique du Pamir donne a penser que la lithosphere venant du sud presente une moins grande anisotropie que la plaque asiatique. Au modele tomographique local s'ajoutent des donnees de tomographie regionale obtenues anterieurement qui elargissent la region tant lateralement qu'axialement. Sous le Pamir, les deux plaques continentales venant du nord et du sud forment une anomalie en forme de larme qui pourrait se delaminer a l'avenir. Sous l'Hindu Kush, nous pouvons clairement suivre la subduction continue quasi verticale du bloc de Katawaz en provenance du sud. Ainsi, la collision continentale sous le Pamir et la subduction sous l'Hindu Kush sont des processus distincts caracterises par des vitesses et directions de deplacement des plaques differentes. [Traduit par la Redaction] Mots-cles : Pamir, Hindu Kush, tomographie sismique, anisotropie, collision continentale, subduction., Introduction Continental collision isa geodynamic process that leads to complex geological and geophysical signatures in the crust and upper mantle. Convergent displacements of large continental plates are responsible for the [...]

The results of numerical experiments with a chemistry–climate model of the lower and middle atmosphere are presented to study the sensitivity of the polar stratosphere of the Northern and Southern Hemispheres to sea surface temperature (SST) variability, both as a result of interannual variability associated with the Southern Oscillation, and because of long-term increases in SST under global warming. An analysis of the results of model experiments showed that for both scenarios of SST changes, the response of the polar stratosphere for the Northern and Southern Hemispheres is very different. In the Arctic, during the El Niño phase, conditions are created for the polar vortex to become less stable, and in the Antarctic, on the contrary, for it to become more stable, which is expressed in a weakening of the zonal wind in the winter in the Arctic and its increase in the Antarctic, followed by a spring decrease in temperature and concentration of ozone in the Antarctic and their increase in the Arctic. Global warming creates a tendency for the polar vortex to weaken in winter in the Arctic and strengthen it in the Antarctic. As a result, in the Antarctic, the concentration of ozone in the polar stratosphere decreases both in winter (June–August) and, especially, in spring (September–November). Global warming may hinder ozone recovery which is expected as a result of the reduced emissions of ozone-depleting substances. The model results demonstrate the dominant influence of Brewer–Dobson circulation variability on temperature and ozone in the polar stratosphere compared with changes in wave activity, both with changes in SST in the Southern Oscillation and with increases in SST due to global warming. [ABSTRACT FROM AUTHOR]

Tropical sea surface temperature (SST) variability, mainly driven by the El Niño–Southern Oscillation (ENSO), influences the atmospheric circulation and hence the transport of heat and chemical species in both the troposphere and stratosphere. This paper uses Met Office, ERA5 and MERRA2 reanalysis data to examine the impact of SST variability on the dynamics of the polar stratosphere and ozone layer over the period from 1980 to 2020. Particular attention is paid to studying the differences in the influence of different types of ENSO (East Pacific (EP) and Central Pacific (CP)) for the El Niño and La Niña phases. It is shown that during the CP El Niño, the zonal wind weakens more strongly and changes direction more often than during the EP El Niño, and the CP El Niño leads to a more rapid decay of the polar vortex (PV), an increase in stratospheric air temperature and an increase in the concentration and total column ozone than during EP El Niño. For the CP La Niña, the PV is more stable, which often leads to a significant decrease in Arctic ozone. During EP La Niña, powerful sudden stratospheric warming events are often observed, which lead to the destruction of PV and an increase in column ozone. [ABSTRACT FROM AUTHOR]

Purpose. To study glutamate metabolism characteristics in phylogenetically different parts of the mammalian brain in experimentally induced hemorrhagic shock (HS) in cats.Material and methods. Experiments were performed on 76 cats. HS was induced by intermittent bloodletting from femoral artery at a rate of 10ml/kg•10 minutes, with the average volume of 24±0.8 ml/kg. The bloodletting was discontinued after arterial pressure (BP) drop to 60.0±1.5 mmHg. We studied ammonia, glutamate (Gt), and α-ketoglutarate (α-KG) levels and glutaminase (GS) and glutamate dehydrogenase (GDG) activity in specimens harvested from phylogenetically different parts of the brain (cortex, limbic system, diencephalon, and medulla oblongata).Results. In intact animals, the peak GDG activity was found in the medulla oblongata (phylogenetically the oldest part of the brain) and the peak GS activity was registered in the sensorimotor cortex (phylogenetically the youngest part of the brain); the glutaminase activity did not depend on the phylogenetic age of brain structures.In the case of HS, Gt metabolism changes began in the sensorimotor cortex manifested by decreased GS activity, which progresses by the 70th minute of the post%hemorrhagic period (PHP) accompanied by delayed increase in the GDG and glutaminase activity, as well as Gt accumulation. In the limbic system and diencephalon the Gt metabolism was changing (impaired glutamine synthesis, stimuled Gt synthesis with glutamine desamidization and α%KG amination) when developed by the 70th minute of the PHP. Similarly to sensorimotor cortex, changes were associated with Gt accumulation. During the agony, α%KG deficiency developed in all parts of the brain as a result of its increased contribution to Gt synthesis. At the same period of time, in the sensorimotor cortex, limbic system and diencephalon the Gt synthesis from glutamine was stimulated, however, the Gt contribution tothe formation of glutamine was decreased. The accumulation of ammonia regardless of the HS stage was detected only inthe sensorimotor cortex, limbic system and diencephalon; in the medulla oblongata ammonium increase was found only during the agony.Сonclusion. HS creates conditions for glutamate accumulation in nerve cells by impairing the metabolism of glutamate in the brain structures. The nature and scope of these disorders depend both on the intensity of glutamate metabolism in phylogenetically different brain structures in acute blood loss and HS.

In this work, the method and prototype for managing the quality of wireless communication channel is presented. The proposed methodology, based on multi-criteria information utility assessment process, is designed. The heterogeneous context awareness data collection subsystems integration is enabled by transforming the acquired data to the highly dynamic intelligent transport systems. Each element of this intellectual transport system runs as a separate component having a specific environmental monitoring and control elements. Evaluation of context information utility allowed realizing the methods and algorithms that adaptively reduce the load on the wireless channel, and the transmitted and stored data volume without losing the enriched contextual information quality, which allows developing more complex heterogeneous services. It is believed that the obtained scientific results will have positive effect for the future research and development of context awareness and service adaptation systems.

This article studies an operational problem arising at a container terminal. Klaipeda city port operations were surveilled up close and relevant remarks were made. The time efficiency of the existing container-lowering procedures using the simulation studies with a test-bed and with a real life crane operation was examined. Statistical analysis of the experimental results has showed that non-automated processes have higher time variance for the lowering process. The operations of quay crane for container handling “ship-to-shore” were analyzed, and lowering procedures time variations were determined. Each container is transported at operators own risk and with pre-defined time efficiency; therefore, it is hard to predict the optimal time for each container handling operation, thus, eventually, additional costs arise. Mathematical model was developed, which described dynamical characteristics of the container movement during lowering procedures. The lowering crane operation was modeled using known dynamic values for each separate case, and the complexity of the problem was proven. The results of modeling and experimental results show that it is possible to achieve optimal values with the existing processes.

Most modern quay cranes operate under the operator’s control. Lifting, lowering, and transporting a container from one platform to another are just some of the actions that a person is responsible for, but the negative consequences of handling can be caused not only by his actions. An error, loading transient instability, or an undervalued environmental factor in the control algorithm can cause a risk to human safety, container, and cargo security. In order to control cargo-handling risk, it is necessary to improve the cargo control systems not only by changing their software, but also by creating additional control algorithms and systems. These systems with programmed control algorithms should be integrated into existing systems to control cargo security and its transfer time. In this article, transient processes and dynamic property of the cargo-handling operation are described and multibody dynamics simulation performed using laboratory prototype of a quay crane. The experimental research performed and integrated autonomous quay crane control algorithm developed with the proposed embedded container swinging control subroutine operated in optimal mode when the control system used PID controller with a feedback including additional PI controller and S-shaped input signal for the analyzed case with the defined parameter set.

A chemistry−climate model of the lower and middle atmosphere is used to compare the role of natural and anthropogenic factors in the observed variability of stratospheric ozone. Numerical experiments have been carried out on several scenarios of separate and combined effects of solar activity, stratospheric aerosol, sea surface temperature, greenhouse gases, and ozone-depleting substances emissions on ozone for the period from 1979 to 2020. Simulations for the past and present periods are compared to the results of ground-based and satellite observations. Estimates of observed trends in column total ozone for the entire period 1980−2018 and separately for the late twentieth and early twenty-first century are presented.

Studied the duration of abstinence from alcohol depending on the level of genetic risk of substance abuse, calculated on the basis of the contribution of genomarkers dopamine system, the 35 adult males who abuse alcohol. It was established that the genetic risk is not associated with the duration of abstinence from alcohol in the conditions of sobriety control.

The Chernobyl accident in 1986 is one of the most large-scale radiation accidents in the world. It led to radioactive contamination of large areas in the European part of the Russian Federation and at the neighboring countries. Now, there are more than 4000 settlements with the total population of 1.5 million in the radioactively contaminated areas of the Russian Federation. The Bryansk region is the most intensely contaminated region. For example, the Krasnogorskiy district still has settlements with the level of soil contamination by cesium-137 exceeding 40 Cu/km2. The regions of Tula, Kaluga and Orel are also significantly affected. In addition to these four regions, there are 10 more regions with the radioactively contaminated settlements. After the Chernobyl accident, the affected areas were divided into zones of radioactive contamination. The attribution of the settlements to a particular zone is determined by the level of soil contamination with 137Cs and by a value of the average annual effective dose that could be formed in the absence of: 1) active measures for radiation protection, and 2) self-limitation in consumption of the local food products. The main regulatory document on this issue is the Federal law № 1244-1 (dated May, 15,1991) «On the social protection of the citizens who have been exposed to radiation as a result of the accident at the Chernobyl nuclear power plant». The law extends to the territories, where, since 1991: – The average annual effective dose for the population exceeds 1 mSv (the value of effective dose that could be formed in the absence of active radiation protection measures and self-limitation in consumption of the local food products); – Soil surface contamination with cesium-137 exceeds 1 Cu/km2. The paper presents results of calculations of the average effective doses in 2014. The purpose was to use the dose values (SGED90) in zonation of contaminated territories. Therefore, the calculations have been done under the assumption that the doses were formed in the absence of active radiation protection measures and self-limitation in consumption of the local food products. The dose to population, rather than the density of radioactive contamination of soil by 137Cs, is the most objective characteristic of the actual radiation exposure to the residents of the contaminated areas.

In this study we present a new regional tomography model of the upper mantle beneath Italy and the surrounding area derived from the inversion of travel times of P and S waves from the updated International Seismological Centre (ISC) catalogue. Beneath Italy, we identify a high-velocity anomaly which has the appearance of a long, narrow "sausage" with a steeply dipping part down to a depth of 400 km and then expanding horizontally over approximately 400 km. Rather than to interpret it as a remnant of the former Tethyan oceanic slab, we consider that it is made up of the infra continental lithospheric mantle of Adria, which is progressively delaminated, whereas its overlying crust becomes progressively accreted into the Apenninic tectonic wedge.

We estimate variations of the crustal thickness beneath the Nepal Himalayas based on tomographic inversion of regional earthquake data. We have obtained a low-velocity anomaly in the upper part of the model down to depths of 40 to 80 km and proposed that the lower limit of this anomaly represents variations of the Moho depth. This statement was supported by results of synthetic modeling. The obtained variations of crustal thickness match fairly well with the free-air gravity anomalies: thinner crust patterns correspond to lower gravity values and vice versa. There is also some correlation with magnetic field: higher magnetic values correspond to the major areas of thicker crust. We propose that elevated magnetic values can be associated with more rigid segments of the incoming Indian crust which cause more compression in the thrust zone and lead to stronger crustal thickening.

The aim of the article. The aim of the research is to improve the methodological approaches to support the rational range of products under today's market conditions. The results of the analysis. Planning and optimization of product mix does not lose its relevance under the current economic conditions. One of the most important tasks in planning is to determine the range of rational perspective to the enterprise product lines products. In this connection there is a need to expand the use of methodological approaches to support the range of products. Integrated application of methodological approaches for determining the rationality and balance the range of products increases the validity of economic decision-making in the field of marketing of the company by identifying the correlation between the profitability of product lines and their weight in the total production. Using the margin profit as a criterion for ranking groups of products with the construction of the Pareto chart allows for a more flexible product strategy, which under the current market conditions is a significant competitive advantage for the enterprise. The necessary conditions for the effective implementation of the proposals of the authors are the high level of consistency of the strategic, tactical and operational levels of management at the enterprise, as well as the analysis of the results of marketing research about customer satisfaction of product parameters. The using of Pareto charts and Spearman correlation coefficient provides increased sales volumes, increasing the target market share of the enterprise, improving the company's image, reducing the risk of marketing activities, increase the company's profit. The results of this study give the company an opportunity to identify deficiencies in a timely manner in the activities and to identify the main directions of improvement of management systems and production planning. Prospects of this study are to develop the tools to facilitate coordination of the results of evaluations of rationality and balance the range of products to the matrices strategic business units of the enterprise. The authors carried out a investigation of rationality and balanced product mix PJSC «Plant named after Frunze». Offers authors regarding sharing between Pareto charts and Spearman coefficient enabled the company to improve the validity of marketing decisions. Conclusions and directions of further researches. Scientific novelty of the authors' proposal is in developing of methodological approaches to the management of product range. Particular attention is given to the study of interrelation between the level of profitability of product lines and the volume of their output.

A checklist of the ’fungus gnat’ group of families in Sciaroidea: Bolitophilidae, Diadocidiidae, Ditomyiidae, Keroplatidae and Mycetophilidae (Diptera) recorded from Finland. At present, the known Finnish fauna comprises 767 recognized species in 78 genera; 21 species of the family Bolitophilidae, 5 of the family Diadocidiidae, 2 of the family Ditomyiidae, 47 of the family Keroplatidae and 692 of the family Mycetophilidae. The unassigned genus Sciarosoma Chandler, 2002 is not included in this paper because it is listed with Sciaridae. The most relevant synonyms, on which species were ever listed from Finland in Hackman (1980) and subsequent authors are indicated in the checklist. Eighteen species names of wrong records were removed.

New faunistic data on fungus gnats (Diptera: Sciaroidea excluding Sciaridae) from Finland and NW Russia (Karelia and Murmansk Region) are presented. A total of 64 and 34 species are reported for the first time form Finland and Russian Karelia, respectively. Nine of the species are also new for the European fauna: Mycomya shewelli Väisänen, 1984, M. thula Väisänen, 1984, Acnemia trifida Zaitzev, 1982, Coelosia gracilis Johannsen, 1912, Orfelia krivosheinae Zaitzev, 1994, Mycetophila biformis Maximova, 2002, M. monstera Maximova, 2002, M. uschaica Subbotina & Maximova, 2011 and Trichonta palustris Maximova, 2002.

The article discusses analyses and assesses the key proposals how to deal with the situation identification for the heterogeneous service support in vehicular cooperation environment. This is one of the most important topics of the pervasive computing. Without the solution it is impossible to adequately respond to the user's needs and to provide needed services in the right place at the right moment and in the right way. In this work we present our developed real time situation identification model for adaptive service support in vehicular communication networks domain. Our solution is different from the others as it uses additional virtual context information source - information from other vehicles which for our knowledge is not addressed in the past. The simulation results show the promising context exchange rate between vehicles. The other vehicles provided additional context source in our developed model helps to increase situations identification level.