• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.880-882
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• 1993

In this paper, a drive circuit for a bifilar-wound hybrid step motor considering mutual inductance and back-emf is investigated. For the suppression circuit, the varition of average torque and torque ripple due to the effect of mutual inductance and back-emf is presented. In order to improve the performance of the motor, a new control scheme is also proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2384-2389
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• 2009

In this paper, we propose a lightweight mutual authentication protocol for secure and efficient home network service. Lee et al. recently proposed an attribute-base authentication key agreement protocol using public key in home network. Its protocol provided forward secrecy but don't diminish conspicious overhead of operation using ticket. Therefore the proposed protocol provided the security and efficiency using hash function and counter. Also it can provide secure home network service by check consumer electronics control level of users after created session key.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1568-1572
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• 2004

This paper proposes a new online calibration algorithm for the array antenna system. As you know, the several previous calibration methods for the mutual coupling did not estimate but measure mutual coupling effect at the real or test-bed system directly. Therefore we suggest some idea to compensate the calibration errors due to mutual coupling effect and mismatch in cables and electronic modules without the off-line calibration. In this work, we can calibrate the array antenna system under the operation of the system using Independent Component Analysis(ICA). This is what is called an online calibration. As you know, the ICA method has permutation and scaling problems. However, we solve problems of the ICA method and apply it to the calibration of an array antenna. The method simultaneously estimates the DOA(Direction of Arrival) of the signals, and calibrates the array for that specific angle. The proposed algorithm is evaluated by computer simulation and its behavior is illustrated by a numerical example.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.5
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• pp.1817-1827
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• 2014

As a new type of wireless network, Ad hoc network does not depend on any pre-founded infrastructure, and it has no centralized control unit. The computation and transmission capability of each node are limited. In this paper, a self-updating one-time password mutual authentication protocol for Ad hoc network is proposed. The most significant feature is that a hash chain can update by itself smoothly and securely through capturing the secure bit of the tip. The updating process does not need any additional protocol or re-initialization process and can be continued indefinitely to give rise to an infinite length hash chain, that is, the times of authentication is unlimited without reconstructing a new hash chain. Besides, two random variable are added into the messages interacted during the mutual authentication, enabling the protocol to resist man-in-the-middle attack. Also, the user's identity information is introduced into the seed of hash chain, so the scheme achieves anonymity and traceability at the same time.

• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.2
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• pp.75-81
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• 2021

This study analyzes the resonance characteristics caused by the mutual interference between LCL filters and the grid impedance under the parallel operation of the grid-connected inverter using the LCL filter. These characteristics are verified through simulation and experiment. Two inverters are used to connect to the grid in parallel, and the system parameters, including the LCL filter, are set to the same conditions. In the case of inverters running in parallel at the point of common coupling, the presence of grid impedance causes mutual interference between the LCL filters of each inverter, and the deviation of the filter resonance frequency is analyzed to understand the parallel inverter. The correlation between the number of devices and the size of grid impedance is simulated by PSIM and verified by MATLAB. By connecting the real-time digital simulator Typhoon HILS to the DSP 28377 control board, the mutual interference characteristics are tested under the condition of two inverters running in parallel. The experimental and analysis results are the same, indicating the validity of the analysis.

• International Journal of Computer Science & Network Security
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• v.23 no.12
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• pp.81-90
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• 2023

Cloud computing is an emerging business model popularized during the last few years by the IT industry. Providing "Everything as a Service" has shifted many organizations to choose cloud-based services. However, some companies still fear shifting their data to the cloud due to issues related to the security and privacy. The paper suggests a novel Trust based Mutual Authentication Mechanism using Secret P-box based Mutual Authentication Mechanism (TbMAM-SPb) on the criticality of information. It uses a particular passcodes from one of the secret P-box to act as challenge to one party. The response is another passcode from other P-box. The mechanism is designed in a way that the response given by a party to a challenge is itself a new challenge for the other party. Access to data is provided after ensuring certain number of correct challenge-responses. The complexity can be dynamically updated on basis of criticality of the information and trust factor between the two parties. The communication is encrypted and time-stamped to avoid interceptions and reuse. Overall, it is good authentication mechanism without the use of expensive devices and participation of a trusted third party.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.1-7
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• 2005

In Chinese philosophy, the concept of Yin and Yang, in the era of the Early China, applies to many more philosophical categories than merely the relationship between the sunny side and the shady side of the sun. A whole series of possible interactions between the Yin and Yang in life is contained in the Chinese Book of Changes, the I Ching. The philosophical theory and the origin of natural sciences of the I Ching is imbued in the Nei Ching. having absorbed and developed the essence of Book of Changes, the Nei Ching reflects the spirit of science. Under the influence of Book of Changes, as well as its idea of Yin and Yang, peculiar at the time, the Nei Ching adapts the essences of the theory of Yin and Yang. The contribution made by the Nei Ching to the development of the philosophical concepts of Yin and Yang lies in that it combines those philosophical concepts with medicine and makes this the basic theory of Chinese medicine. In the Nei Ching, the Yin and Yang theory asserts that the human body is an organic whole, and there exists an organic connection between all tissues and structures. Therefore, the Yin and Yang functions as an essential life that plays a major role of the organic interrelation, the mutual control, and the mutual assistance. Yet, at the same time, each of them can be divided into the opposite aspects of yin and yang. Yin and yang depend on each other for existence. Without yin, there would be no yang, Without yang, there would be no yin. Neither can exist in isolation. Thus the interrelation of Yin and Yang is premised on the two opposite forces and aspects as the underlying cause of all change of Yin and Yang.

• Journal of the Korea Computer Industry Society
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• v.7 no.4
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• pp.271-280
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• 2006

This study is to propose and design a protocol that offers independent authentication with no necessity of certification authority using password between participants in RS_RCCS(Relay Service-based Remote Computing Control System). In RS_RCCS without authentication center that remote service requesters have mutual authentication with many service managers, there needs for a protocol protected from password attacks. Hereupon, this study is to offer an efficient authentication setting and a protocol for RS_RCCS and helpful for the usefulness of resource management.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.3
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• pp.194-199
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• 1996

평면 배열형 소나 센서에서는 트랜스듀서 상호간의 간섭효과들이 음을 방사하는 각각의 트랜스듀서 및 평면 배열의 빔패턴에 영향을 주게된다. 따라서 음향 방사출력의 계산은 소나용 트랜스듀서의 성능및 효율을 평가하는데 필수적이다. 음향 방사출력을 예측하기 위하여 무한 강성 배플에 고정된 수개의 트랜스듀서를 이론해석의 대상으로 설정하였다. 각 트랜스듀서는 자기방사 임피던스 및 상호방사 임피던스로 구성되어 있으며 이것의 총 방사 임피던스 및 음향반사 출력의 추출은 등가 전기회로 모델을 이용하였다. 이론및 수치해석의 결과에 근거하여 음향방사 출력은 각 트랜스듀서 상호간의 간섭의 양에 의존함을 보였으며 상호간섭에 의한 음향출력 손실은 25.05%에서 최고 51.52%정도임을 확인하였다.

• Journal of information and communication convergence engineering
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• v.4 no.1
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• pp.28-35
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• 2006

In this paper, we propose to synchronization method for mutual cooperative control method that have unstable limit cycles in a chaos trajectory surface in the chaotic UAVs. We assume all obstacles in the chaos trajectory surface have a Van der Pol equation with an unstable limit cycle. We also show computer simulation results of Arnold equation, Chua's equation trajectories with one or more Van der Pol as a obstacles. We proposed and verified the results of the method to make the embedding chaotic UAV to synchronization with the chaotic trajectory in any plane.