• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.12
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• pp.1670-1679
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• 1995

In this paper, an optimal variable structure controller with a multilayer neural inverse identifier is proposed. A multilayer neural network with error back propagation learning algorithm is used for construction the neural inverse identifier which is an observer of the external disturbances and the parameter variations of the system. The variable structure controller with the multilayer neural inverse identifier not only needs a small part of a priori knowledge of the bounds of external disturbances and parameter variations but also alleviates the chattering magnitude of the control input. Also, an optimal sliding line is designed by the optimal linear regulator technique and an integrator is introduced for solving the reaching phase problem. Computer simulation results show that the proposed approach gives the effective control results by reducing the chattering magnitude of control input.

• The Journal of Society for e-Business Studies
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• v.18 no.3
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• pp.107-123
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• 2013

In a wireless sensor network environment, it is required to ensure anonymity by keeping sensor nodes' identifiers not being revealed and to support real-time authentication, lightweight authentication and synchronization. In particular, there exist possibilities of location information leakage by others, privacy interference and security vulnerability when it comes to wireless telecommunications. Anonymity has been an importance issue in wired and wireless network environment, so that it has been studied in wide range. The sensor nodes are interconnected among them based on wireless network. In terms of the sensor node, the researchers have been emphasizing on its calculating performance limit, storage device limit, and smaller power source. To improve of biometric-based D. He scheme, this study proposes a real-time authentication protocol using Unique Random Sequence Code(URSC) and variable identifier for enhancing network performance and retaining anonymity provision.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.9
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• pp.1040-1049
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• 1992

When the model of control object is not described correctly, ambiguity is often expressed by unknown parameter, In a case that this ambiguity satisfies a certain condition of limit, if robust control method is used, even if model is not correctly discribed, control system can be composed. The characteristic of control based on the variable structure theory is that the influence by ambiguity of system eradicates high-gain feedback. Therefore in this paper, VSS indentifier is proposed. Transformation of control input producing control system in sliding mode actually reflects influence of ambiguity unknown parameter of control object. If useful information is out from transformation input by a few times of operation, proper identify mechanism is selected and this information is used, to decide the unknown parameter is possible. So more effective controller was composed by addition of the proposed identifier to the unknown parameter identifier of robot manipulator.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10a
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• pp.159-165
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• 1998

In this paper the sway-control problem of a container crane is investigated. The control loop is divided into two stages. The first stage is a modified time optimal control for trolley traversing. The velocity command for trolley traversing consists of three components ; a reference velocity and two feedback signals for compensating the deviations of trolley and sway angle from their desired trajectories. For trolley's exact positioning the trolley dynamics is identified via an error equation identifier structure. The second stage is a nonlinear residual sway control that starts at the end of first stage. The control design for the second stage is investigated from the perspective of controling an underactuated system, and the control law combines the feedback linearization and variable structure control.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2008-2011
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• 1998

When the vector control, which does not need a speed signal from a mechanical speed sensor, it is possible to reduce the cost of the control equipment and to improve the control performance in many industrial application. This paper describes a rotor speed identification method of induction motor based on the theory of Model Reference Adaptive System(MRAS). The identifier execute the rotor speed identification so that the vector control of the induc-tion motor may be achieved. The improved auxiliary variable are introduce to perform accurate rotor speed identification. Simulation and experimental result show the validity of the proposed control method.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.2
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• pp.195-203
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• 2016

In order to overcome the influence of system stability and accuracy caused by uncertainty, estimation errors and external disturbances in Eight-Rotor MAV, L2 gain control method was proposed based on interval type II fuzzy neural network identification here. In this control strategy, interval type II fuzzy neural network is used to estimate the uncertainty and non-linearity factor of the dynamic system, the adaptive variable structure controller is applied to compensate the estimation errors of interval type II fuzzy neural network, and at last, L2 gain control method is employed to suppress the effect produced by external disturbance on system, which is expected to possess robustness for the uncertainty and non-linearity. Finally, the validity of the L2 gain control method based on interval type II fuzzy neural network identifier applied to the Eight-Rotor MAV attitude system has been verified by three prototy experiments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.4
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• pp.709-719
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• 2015

This paper introduces a proper renaming service using variable action and security services against the analysis techniques in Java code. The renaming service that is introduced is separated into API pattern and loop condition. We present our scheme algorithm with known Java obfuscation techniques and tools in order to help readers understanding, and implement prototype to prove practicality in this paper. Test result using prototype shows 73% successful variable renaming rate. Using our scheme, cooperators can intuitionally understand all of code. Also, It helps malware analysts to predict malware action by variable name. But application source code that is developed by Java is exposed to hackers easily using our scheme. So we introduce Java application code protection methods, too.

• The Journal of Information Systems
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• v.22 no.4
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• pp.49-69
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• 2013

Recently, enterprises have reinforced security control in order to prevent infringement of personal information and abuse of customer information by insiders. However, the reinforcement of security control by enterprises makes it difficult for internal users to perform business by using a business information system. There is, therefore, a need for research on various fields, which makes it possible to establish an appropriate security control policy while minimizing an impact on business. The present research verifies and analyzes an impact on difficulty in business of internal users using customer information, which is caused by security control performed by display restriction on customer information identifiers. The present research is intended to academically develop a technique for statistically analyzing an impact degree and a causal relationship between security control and an impact on business, which is a dichotomous variable, and to practically contribute to the establishment of an efficient security policy in consideration of an impact on business when an enterprise applies security control. A research target was internal business information systems of domestic securities enterprises, data was collected by questionnaire, and verification/analysis was performed by logistic regression analysis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.28 no.1
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• pp.38-43
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• 2017

This study analyzes the role of the Sorting Hat in structuring the identity of the characters in the Harry Potter series written by J. K. Rowling. In the different stages of adolescence, one explores and re-establishes one's identity. One's sense of identity is determined by the commitments made regarding personal and social traits. However, it is difficult to establish a concrete identity formation process theory that is communicable to adolescents. In Harry Potter, the characters' identities are reflected upon the Sorting Hat and are continuously molded throughout the book. The Sorting Hat provides nurturing experiences based on temperament. Based primarily on their temperament, it sorts the students into four houses, each with their own distinct characteristics. Once sorted, the houses become the living and learning communities in which the students share the same dormitory and classes until their graduation. Within the community, the students seek connections, supportive relationships, and understanding within the group. The taking on of the group identity is an explanatory variable in the formation of individual identity. The Sorting Hat provides the students with stability and a safe boundary. After being sorted based on their temperament, the inexperienced and immature adolescents can explore different options under the guidance of the Hat before making a definite commitment. By presenting them with an appropriate environment (such as a mentor, friend, or family member), the Hat further shapes their identity and integrates the identity elements ascribed in the beginning. By providing experiences and interactions based on their unique temperament and environment, the Sorting Hat plays a crucial role in establishing the students' identities. The Sorting Hat can be an ideal model for finding one's identity during adolescence.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.70-74
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• 2007

National R&D Projects provide the central axis to weave the valuable information derived from variable projects and their participants. Thus to efficiently manage and utilize the National R&D information, the project-oriented management system has to be established and its information must to be articulated with each other. Using the connected relations the system can provide an efficient way to easily gain and share the information. To do this the National R&D information management systems and the identifier management system must to be builded and the common services and functions connecting the systems have to be provided. On this study, by defining these constituents and their relationships we're going to establish the base of promotion of National R&D Information utilization.