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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 [...]