On the Flexibility of Deployable Dome Structures and their Application in Architecture

In this paper we discuss flexibility and applicability of deployable dome structures in contemporary architecture. A deployable dome is a spatial structure derived from appropriately connected planar polygonal panels. Nowadays, deployable domes are little researched comparing to other deployable structures, such as pseudo-cylinders, for example. When designing these configurations, either changeable supports' spans or strain of some structural elements might occur, depending on the underlying geometrical analysis. Such occurrences, usually being undesirable, can be avoided by the adequate geometrical solution which can also satisfy various sizes of the structures. Therefore, they could answer the purpose both in architectural and urban design. Thus, choosing suitable dimension of the structure, numerous applications can be obtained, starting from street furniture to large scale convertible structures for covering open spaces

Modeling of thermoelectric module operation in inhomogeneous transient temperature field using finite element method

This paper is the result of research and operation modeling of the new systems for cooling of cutting tools based on thermoelectric module. A copper inlay with thermoelectric module on the back side was added to a standard turning tool for metal processing. For modeling and simulating the operation of thermoelectric module, finite element method was used as a method for successful solving the problems of inhomogeneous transient temperature field on the cutting tip of lathe knives. Developed mathematical model is implemented in the software package PAK-T through which numerical results are obtained. Experimental research was done in different conditions of thermoelectric module operation. Cooling of the hot module side was done by a heat exchanger based on fluid using automatic temperature regulator. After the calculation is done, numerical results are in good agreement with experimental. It can be concluded that developed mathe-matical model can be used successfully for modeling of cooling of cutting tools

Non-linear transient heat conduction analysis of insulation wall of tank for transportation of liquid aluminum

This paper deals with transient non-linear heat conduction through the insulation wall of the tank for transportation of liquid aluminum. Tanks designed for this purpose must satisfy certain requirements regarding temperature of loading and unloading, duringtransport. Basic theoretical equations are presented, which describe the problem of heat conduction finite element analysis, starting from the differential equation of energy balance, taking into account the initial and boundary conditions of the problem. General 3-D problem for heat conduction is considered, from which solutions for two- and one-dimensional heat conduction can be obtained, as special cases. Forming of the finite element matrices using Galerkin method is briefly described. The procedure for solving equations of energy balance is discussed, by methods of resolving iterative processes of non-linear transient heat conduction. Solution of this problem illustrates possibilities of PAK-T software package, such as materials properties, given as tabular data, or analytical functions. Software alsooffers the possibility to solve non-linear and transient problems with incremental methods. Obtained results for different thicknesses of the tank wall insulation materials enable its comparison in regards to given conditions

Automated Fingerprint Identification System: with and without the Possibility of Correction of a Digitalised Image

According to the fact that systems for automatic processing of biometric data are constantly advancing in terms of speed and reliability, as well as in terms of adding new processing capabilities, the question of choosing the appropriate system becomes more important. In this paper the idea is to present the technical and technological solutions of the Automated Fingerprint Identification System with different operating principles, with and without the possibility of correction or coding of a digitized image. Comparisons of different systems were performed in test and production environments. The test database with 10 000 records and about half a million records of dactyloscoped persons in the production of database for testing the performance of search was used. The results have shown that there exists a statistically significant difference (p < 0.001) between examined systems in face fingerprint search according to latent fingerprint databases (which means indirect verification). In the production environment, it was found that there exists statistically significant difference (p < 0.001) in the direct and indirect verification showing advantages and disadvantages of the compared systems

Calculation of temperature fields during lathe machining with thermoelectric cooling by using the finite element method

© 2018 Serbian Society of Heat Transfer Engineers. The aim of this work is to explore the possibilities of the implementation of systems based on a thermoelectric module for cooling the cutting tool. This cooling becomes significant when it is not possible to use conventional coolants and lubricants. Starting from existing mathematical models for the calculation of the temperature field of the cutting tool, a mathematical model is developed that takes into account the cooling based on the thermoelectric module. The use of the finite element method determines temperature field when dry lathe machining in the cooling conditions based on the thermoelectric module. The Software package, PAK-T, is used for the calculations and was developed at the Department of Applied Mechanics, Faculty of Engineering in Kragujevac. The system for cooling the cutting tool based on the thermoelectric module was realised under laboratory conditions on a prototype model, which consists of a cutting tool and a thermoelectric module. Verification of the obtained results was carried out on the basis of a mathematical model by experimental research of the temperature field of the cutting tool in terms of cooling based on a thermoelectric module

EXPERIMENTAL TESTING OF THERMOREGULATING TEXTILE CLOTHES WITH MICROENCAPSULATED ORGANIC PHASE CHANGE MATERIALS

Abstrac

Evidence of recombination in Tula virus strains from Serbia

Tula hantavirus (TULV) belongs to Bunyaviridae family, with negative sense RNA genome. Segmented nature of hantaviral genome allows for genetic reassortment, but the evidence of homologous recombination also exists. In this study we analyzed TULV sequences isolated in Serbia on different occasions and from different rodent hosts: 1987 strain from Microtus subterraneus and 2007 strain from Microtus arvalis. Phylogenetic analysis of both L and S segment sequences is suggestive of geographically related clustering, as previously shown for majority of hantaviruses. Reconstruction of phylogenetic tree for TULV S segment showed that both sequences from Serbia clustered together with sequences from East Slovakia, which had previously been shown to be recombinants (Kosice strain). Exploratory recombination analysis, supported by phylogenetic and amino acid pattern analysis, revealed the presence of recombination in the S segment sequences from Serbia, resulting in mosaic-like structure of TULV S segment similar to the one of Kosice strain. Although recombination is considered a rare event in molecular evolution of negative strand RNA viruses, obtained molecular data in this study support evidence of recombination in TULV, in geographically distant regions of Europe. (C) 2013 Elsevier B.V. All rights reserved