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Reaching of negative temperatures for various applications such as food industry, medicine or experimental physics implies the use of cryogenic fluids (especially liquid nitrogen) or refrigeration heat pumps. The technological progress in materials science in the last years allowed the development of other methods to obtain low temperatures needed for such applications, by means of using the Peltier effect. The Peltier modules were developed and perfected in last decades, in order to allow temperature differences of 20 ºC to 85 ºC between the two faces of one module when one side is kept at room temperature, and an electric current is supplied. Thus, the possibility of developing devices which allow obtaining and controlling temperatures up to -50 ºC were opened, eliminating all the difficulties related to the use of cryogenic agents, which imply the need of Dewar storage vessels, cryogenic transfer lines and controlling of cryogenic liquid such as liquid helium or liquid nitrogen (with boiling temperature of -196 ºC, at atmospheric pressure) or refrigeration systems. In this work are presented the design, execution and testing results of a thermally controlled enclosure aimed for the calibration of temperature sensors, in the range of -50 to +20 ºC, using Peltier modules. Despite the high electric power consumption of the Peltier modules needed to cool down the enclosure due to the low COP (coefficient of performance) compared to the conventional refrigeration systems, this approach in obtaining negative temperatures presents important advantages such as the lack of maintenance, low volume, simplicity of temperature control and high temperature stability (0.1 ºC). [ABSTRACT FROM AUTHOR]

The use of high temperature superconducting materials (HTS) in various applications, requires knowledge of their critical parameters like critical current, critical magnetic field and critical temperature, in DC applications like high magnetic field generators, superconducting magnetic energy storage system (SMES), magnetic resonance imaging (MRI), magnets for particle accelerators, SC Maglev trains and other applications. Also, these parameters are important for specific properties in alternating current applications like fault current limiters, transformers, generators, motors, and power transmission lines. An important characteristic that needs to be tucked into consideration for AC applications is the power losses that occur in the HTS superconducting materials, which limits the maximum performance that the superconducting materials can attain for these applications. In order to measure these characteristics, which depend on the type of material used, but also on the temperature and other parameters, it is necessary to use an appropriate setup device that allows both obtaining the working temperature range (4.2 K to 300 K and other necessary parameters like high vacuum 10-6 mbar, high current supply (500 A), high magnetic field measurement system (1-10 T), etc. For the cryogenic cooling of the entire system, a closed cycle Gifford-McMahon type cryocooler is used, with two cooling stages, stage I at 50 K and second stage at 4.2 K (liquid Helium temperature). The set-up system used for measurement of the parameters of HTS superconducting materials (YBCO, BSCCO or MgB2) and the various coils made with them, is described in this article together with its functional parameters and some experimental results obtained by testing an YBCO coils system. The maximum generated magnetic flux density was 5 T in the centre of the coils system. [ABSTRACT FROM AUTHOR]

Copyright of Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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.)

National security programmatic documents have, among other, the role of highlighting the most relevant risks, threats and vulnerabilities that decision-makers, benefiting from the technical expertise of specialized structures, consider relevant for national security at some point, but also the priorities that the State's external action and its action in the field of security must pursue for the duration covered by each strategy of the respective State. Basically, reading a security strategy can directly place the reader in the time it was issued, and the reading all of these documents, in their temporal succession, provides an overview of the evolution of the political and security situation of the State concerned, for a given time frame. Through the present study we propose to provide such a picture at the center of which the concept of good governance is located. [ABSTRACT FROM AUTHOR]

In the democratic societies of European or Euro-Atlantic tradition, the principle according to which sovereignty belongs to the people, and that it is exercised through its elected representatives, means that the people, through their representatives, must also exercise an effective control over the security sector. For this reason, the European and Euro-Atlantic democratic tradition has established certain mechanisms of control. Their general features, as they are presented in the official acts of international organisations and in the specialised doctrine, and their concrete application, in the Romanian Constitution or in the acts regulating its application, are analysed in the article. [ABSTRACT FROM AUTHOR]

Copyright of Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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 Synthesis of Theoretical & Applied Mechanics / Sinteze de Mecanică Teoretică și Aplicată is the property of Matrix Rom 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.)

Lateral oscillation of railway vehicles is a major problem for narrow gauge railways or metric because reduced diameter bogie wheels. This problem can be reduced by changing the Prud'homme limit on vehicles and improving resistance tread lateral, being able to use the checkrails. Running with lateral oscillations road of the railway vehicles passenger and freight is a known problem for standard gauge railways. The lateral movement represents a particular problem which causes passengers discomfort and in major cases, the operating speed must be reduced. Whilst the railways and trains may suffer because of this. A possibility to resolve these problems should as reducing the Prud'homme limit, which defines the permissible lateral load, repeated exerted on the rail. This formula was used for vehicles and standard gauge railways, but many companies and suppliers of rolling stock have assumed that can be applied on narrow gauge lines. On the basis of existing information, without being made field tests or computer simulations, Prud'homme limit can be modified to standard gauge rail networks, but to verify the load lateral of this type of gauge must be made more investigations. Inevitably have emerged more simplistic assumptions, but is unlikely to significantly alter the conclusions. [ABSTRACT FROM AUTHOR]

The railway vehicles are characterized by the fact that the wheel axle moves in the path of travel and self guidance in the contact forces between the tire rim and wheel tracks. Following wheels, besides the three common features they have and other land vehicles, namely support vehicle vertically, running about and propulsion, respectively braking railway vehicles in addition their specific function, namely self guidance that the two wires inside of rail. Being metallic wheels and also the rails that give the vehicle the ability to rail loadings much higher than other land vehicles. This capability, combined with that of self guidance, creates the possibility of forming convoys of vehicles (trains) heavy, giving wheel system - advantages of high capacity rail transport. The study and thorough understanding of the complex phenomena of the contact wheel - rail is actually the fundamental problem that ensures the development of railway vehicles. [ABSTRACT FROM AUTHOR]

In the case of locomotives intended to carry passengers traffic (as the case locomotive of the series BR 185), engine vehicle is subjected to high dynamic loads. One of these dynamic phenomena is known in the literature, the phenomenon of hunting. By hunting means coupling the lateral oscillations of hunting. Hunting oscillations occur when a vehicle maintained and increasing lateral oscillations develop due to sub-assemblies, ie the reactions of the resultant forces that interact with the machine running and the axle drive system engine and the suspension and damping floors. One of the significant features of the hunting phenomenon lies in the fact that it is composed oscillations occur even in the case of perfect track. [ABSTRACT FROM AUTHOR]