In this paper we introduce an UHF-RFID reader system built to serve as a multi-purpose reader for UHF-RFID applications. The structure of the reader itself is highly flexible to be able to include several standards. The intended use of the reader, however, consists in the support of navigation systems for the indoor environment. Assuming that arbitrarily distributed RFID tags, containing their exact positions given in latitude, longitude and elevation, are read out by the reader, the system is able to achieve the tags positions. In that case, the reader is able to evaluate and forward the readout positions in order to notify a superior navigation system of the estimated position, obtained from the RFID tags. This will lead to a more robust navigation system being able to navigate even in a high-grade multipath environment. Anyway, this paper concentrates more on technical terms concerning the reader system, including signal and spectrum analysis
This paper offers an RFID-based indoor navigation application which utilizes cell phones with an RFID extension and distributed RFID tags fixed to interior equipment. This combination creates a special navigation environment which helps pedestrians to orient oneself in new respectively unknown environments. Therefore, each RFID tag contains information about the current position, location or an unknown environment. Thus, the current position can be determined, which is the basic for navigation. A further advantage of this application is the availability of additional graphical data stored on the RFID tags. This additional graphical data contains global information about the indoor environment and also local graphical information about the near environment of the RFID tag. This yields to an RFID-based navigation system, that not only shows the current position but also the near environment surrounding that specific location. Therefore, this systems grants navigation assi stance by leading the user step-by-step or rather tag-by-tag to the final destination
Introduction. Torsional vibrations caused by drilling using a polycrystalline diamond compact (PDC) bit are analysed using wellbore data obtained under various drilling modes. The drilling caused by torsional vibrations are analysed. Two types of torsional vibrations, including those caused by the cutting action of a bit and by frictional forces.Aim. To investigate the induction of torsional vibrations as a result of rock destruction by PDC bits.Materials and methods. The research methodology was based on “Richard-Germay-Detournay” and “Tian-Detournay” bit designs and methods for reducing the critical effects of torsional vibrations induced by PDC bits during rock destruction.Results. Statistical analysis has shown that the drilling efficiency of the bit (DE) correlates well with the occurrence of torsion vibrations caused by the bit. The aggressiveness of the cutting structure of the PDC bit can be represented by an average DE rating. If the PDC bit is designed so that its DE exceeds a critical value, then the occurrence of torsion vibrations on the bit is unlikely during drilling.Conclusion. When drilling with a polycrystalline diamond PCD bit, two types of vibrations occur. If torsional vibration occurs due to the cutting action of the bit, then the fight against this process is focused on the design of the bit and operational parameters, the load on the bit and the speed of rotation of the bit. If the torsional vibration is caused by friction, vibration reduction methods should be focused on changing the design of the BHA and the drill string or the profile of the well. Therefore, it is very important to determine whether the torsional vibration is caused by the friction force of the elements, the cutting action of the bit, or both. In drilling, it is always necessary to search for the maximum penetration speed by changing the load on the bit under specified drilling conditions. To do this, it is necessary to evaluate the drilling efficiency of the DE bit, therefore, this article has evaluated the parameter depending on the size of the bit, which will determine the critical value of the drilling efficiency parameter.
For study of the character of technogenic pollution impact on physical development of adolescents, there were estimated body length and weight, the weight and growth index, Quetelet and Rohrer indices and blood pressure in 14-year old girls and boys from birth living in the mid-latitudes (Cities of Yaransk, Kirov) or in the European North conditions (s. Sedyu, City of Ukhta) at different levels of technogenic pollution: suspended matter, SO2, CO, NO2, formaldehyde and benzo(a)perrin in free air. Comparison of the adolescents in Sedyu and Yaransk living under the low-level technogenic pollution has shown no impact of the European North conditions on the physical development indices. Comparison of the adolescents in Yaransk and Kirov as well as in Sedyu and Ukhta has shown that the high level of technogenic pollution in the mid-latitude conditions delayed physical development, and in the European North conditions, it did not have similar effect, that was explained by the phenomenon of cross-adaptation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.