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Kim, Keewon;Park, Kyungmin;Park, Tae-Keun
- Journal of the Korea Society of Computer and Information
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- v.26 no.9
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- pp.81-88
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- 2021
In this paper, we analyze the possibility of deregistration attack in 5G SNPN (Standalone Non-Public Network) based on 3GPP standard document. In the deregistraion attack, the attacker pretends to be a UE that is normally registered with AMF (Access and Mobility Management Function) and attempts to establish a spoofed RRC (Radio Resource Control) connection, causing AMF to deregister the existing UE. The existing deregistration attack attempts a spoofed RRC connection to the AMF in which the UE is registered. In addition, this paper analyzes whether deregistration attack is possible even when an attacker attempts to establish a spoofed RRC connection to a new AMF that is different from the registered AMF. When the 5G mobile communication network system is implemented by faithfully complying with the 3GPP standard, it is determined that a deregistration attack of a UE is impossible.
https://doi.org/10.9708/jksci.2021.26.09.081 인용 PDF KSCI HTML

Seo Jong-yun;Yang Hyong-yeol;Kim Kwang-Heon;Lim Young-Cheol;Cha Hyun-Rok;Jang Do-Hyun
- Proceedings of the KIPE Conference
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- 2001.10a
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- pp.351-354
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- 2001
In this paper, we present self-tuning control of switched reluctance motor for maximum torque with phase current and shaft position sensor. Determination method of turn-on/off angle is realized by using self-tuning control method. During the sampling time, micro-controller checks the number of pulse from encoder and compare with the number of pre-checked pulse. After micro-controller calculates between two data, it moves forward or backward turn-off angle. When the turn-off angle is fixed optimal turn-off angle, the turn-on angle automatically moves forward or backward by a step using self-tuning control method. And then, optimal turn-off angle is searched once again. As such a repeating process, turn-on/off angle is moved automatically to obtain the maximum torque. The experimental results are presented to validate the self-tuning algorithm.
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Cha, Hyun-Rok;Seo, Jong-Yun;Yang, Hyong-yeol;Kim, Kwang-Heon;Lim, Young-Cheol;Jang, Do-Hyun
- Journal of Power Electronics
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- v.1 no.1
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- pp.56-64
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- 2001
This paper presents the switching angle and voltage for maximizing the torque or efficiency and minimizing torque ripple of an 8/6, SRM. The approximate analysis and computer simulation determine the switching angle and voltage by using SIMULINK$^\textregistered$. This is performed as a function of the speed and torque required by the load. From the results, new three facts can be known: First, the maximum torque depends on voltage and speed depends on switching angle. The others, the maximum efficiency and minimum torque ripple relay on switching angle. We control the switching angle and voltage of and asymmetrical inverter for the SRM with one-chip micro controller.
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