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Copyright of Proceedings of the International HVAC&R Congress is the property of Union of Mechanical & Electrotechnical Engineers & Technicians of Serbia (SMEITS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work the dynamic fracturing of an ultra-high strength cementitious material is probed with in-situ ultra-high speed X-ray phase-contrast diagnostics to investigate the phenomenology of dynamic fracture. Gas gun experiments were conducted on two characteristic samples with two different impact speeds, namely 80 and 190 m/s using the edge-on impact test configuration. The samples were placed within the intense X-ray beam providing an observation field of 12.8 mm in width and 8 mm in height. Thanks to equispaced 16 bunches of short X-ray pulses, the samples were imaged through an indirect detector arrangement using the Shimadzu HPV-X2 camera lens-coupled to a fast scintillator capturing through-thickness measurements with an interframe time of 1.06 μs. The comparison of fragmentation patterns between two samples revealed an important insight into velocity dependant spall formation as well as the effects of crack closure and bridging. [ABSTRACT FROM AUTHOR]

Copyright of International Symposium 'Modern Trends in Livestock Production' is the property of Institute for Animal Husbandry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Symposium 'Modern Trends in Livestock Production' is the property of Institute for Animal Husbandry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main goal of this paper is to emphasize the importance, types and potentials of educational tourism for the sustainable development of Serbia. We will start from the concept of sustainable development, and continue by looking at the educational tourism concept holistically, as a tool to improve the quality of education, to strengthen the connection with the local community, to develop all children's potential and to get them to learn and know more about their local community and be more involved, thus emphasizing the concept of an active citizen who takes responsibility for personal and social growth and development. The results we obtained after studying this issue have pointed to the need to develop educational programs for various tourist destinations, to improve accommodation, work methods and techniques, and to provide better training for the tourist guides in order for them to be able to practice different types of educational tourism. The importance of educational tourism for the sustainable development of tourism in Serbia needs to be supported and promoted through various promotions, actions, projects and the exchange of good practices. [ABSTRACT FROM AUTHOR]

This paper presents the measurement results of the dynamic tensile strength of a High Performance Concrete (HPC) obtained using full-field identification method. An ultra-high speed imaging system and the virtual fields method were used to obtain this information. Furthermore the measurement results were compared with the local point-wise measurement to validate the data pressing. The obtained spall strength was found to be consistently 20% lower than the one obtained when the Novikov formula is used. [ABSTRACT FROM AUTHOR]

Ceramic materials are numerically studied to understand their fracturing behaviour upon dynamic conditions and impact loadings. During a ballistic impact of a projectile against a ceramic armour system, an intense fragmentation composed of numerous oriented cracks, develops in the target. It is the reason why the conditions of crack initiation, propagation and arrest in these materials need to be investigated. In the present work, a dynamic testing configuration has been developed in order to characterise the dynamic fracture toughness (KI,d), considering a single crack that propagates from the specimen notch tip. The "Rockspall" testing technique, which employs a two-notch specimen loaded in a spalling experiment, was used. Thanks to the reflection of a compression wave into a tensile load from the sample free-end, a single dynamic crack is triggered. The sample geometry is optimised by means of a series of FE numerical simulations involving an anisotropic damage model. [ABSTRACT FROM AUTHOR]