• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.1
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• pp.81-87
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• 2012

Intrusion Detection System that protects system safely is necessary as network technology is developed rapidly and application division is wide. Intrusion Detection System among others can construct system without participation of other severs. But it has weakness that big load in system happens and it has low efficient because every traffics are inspected in case that mass traffic happen. In this study, Distributed Intrusion Detection System based on protocol is proposed to reduce traffic of intrusion detection system and provide stabilized intrusion detection technique even though mass traffic happen. It also copes to attack actively by providing automatic update of using rules to detect intrusion in sub Intrusion Detection System.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1332-1341
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• 1999

Rapid expansion of network and increment of computer system access cause computer security to be an important issue. Hence, the researches in intrusion detection system(IDS)are active to reduce the risk from hackers. Considering IDS, we propose a new IDS model(DABIDS : Distributed Agent Based Intelligent intrusion Detection System) based on distributed intrusion detecting agents. The DABIDS dynamically collects intrusion behavior knowledge from each agents when some doubtable behaviors of users are detected and make new agents codes using intrusion scenario data base, and broadcast the detector codes to the distributed intrusion detecting agent of all node. This DABIDS can efficiently solve the problem to reduce the overhead for training detecting agent for intrusion behavior patterns.

• Journal of Power Electronics
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• v.18 no.5
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• pp.1513-1522
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• 2018

This paper proposes a new islanding detection method for inverter-based distributed generators by continuously injecting a negligible amount of 2nd order harmonic current. The proposed method adopts a proportional resonant (PR) controller for the output current control of the inverter, and a PR filter to extract the 2nd order harmonic voltage at the point of common coupling (PCC). The islanding state can be detected by measuring the magnitude ratio of the 2nd order harmonic voltage to the fundamental voltage at the PCC by injecting a 2nd order harmonic current with a 0.8% magnitude. The proposed method provides accurate and fast detection under grid voltage unbalance and load unbalance. The operation of the proposed method has been verified through simulations and experiments with a 5kW hardware set-up, considering the islanding test circuit suggested in UL1741.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.2 no.3
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• pp.135-149
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• 2008

Traditional attack detection schemes based on packets or flows have very high computational complexity. And, network based anomaly detection schemes can reduce the complexity, but they have a limitation to figure out the pattern of the distributed global scale network attack. In this paper, we propose an efficient and fast method for detecting distributed global-scale network attack symptoms in high-speed backbone networks. The proposed method is implemented at the aggregate traffic level. So, our proposed scheme has much lower computational complexity, and is implemented in very high-speed backbone networks. In addition, the proposed method can detect attack patterns, such as attacks in which the target is a certain host or the backbone infrastructure itself, via collaboration of edge routers on the backbone network. The effectiveness of the proposed method are demonstrated via simulation.

• Journal of Sensor Science and Technology
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• v.24 no.1
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• pp.1-5
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• 2015

The V-grooved single-mode fiber in which a surface part of the core was removed was investigated as a quasi-distributed water detection sensor. In the normal state, the V-grooved region is filled and covered with a specific RI (Refractive Index)-matched medium, and the sensor experiences minimal optical loss. As water invades the V-grooved region, the material is dissolved and removed, and a considerable optical loss occurs owing to the large RI difference between the fiber core and water. The experimental results showed the feasibility of the device as a sensor element of the quasi-distributed water detection sensor system based on general optical time domain reflectometry (OTDR).

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1153-1156
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• 1987

This paper presents a distributed algorithm for deadlock detection in distributed computing system. The deadlock could be detected optimally from cycle. This algorithm maintains the Process-Resource Table and it could be found the deadlock from the table.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1577-1580
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• 2005

With remarkable growth of using Internet, attempts to try intrusions on network are now increasing. Intrusion Detection System is a security system which detects and copes illegal intrusions. Especially with increasing dispersive attacks through network, concerns for this Distributed Intrusion Detection are also rising. The previous Intrusion Detection System has difficulty in coping cause it detects intrusions only on particular network and only same segment. About same attacks, system lacks capacity of combining information and related data. Also it lacks cooperations against intrusions. Systematic and general security controls can make it possible to detect intrusions and deal with intrusions and predict. This paper considers Distributed Intrusion Detection preventing attacks and suggests the way sending active packets between nodes safely and performing in corresponding active node certainly. This study suggested improved E-IDS system which prevents service attacks and also studied sending messages safely by encoding. Encoding decreases security attacks in active network. Also described effective ways of dealing intrusions when misuses happens thorough case study. Previous network nodes can't deal with hacking and misuses happened in the middle nodes at all, cause it just encodes ends. With above suggested ideas, problems caused by security services can be improved.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.502-512
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• 2016

The wireless carrier sense multiple access with collision detection (WCSMA/CD) and carrier sense multiple access with collision resolution (CSMA/CR) protocols are considered representative distributed collision detection protocols for fully connected dense wireless local area networks. These protocols identify collisions through additional short-sensing within a collision detection (CD) period after the start of data transmission. In this study, we analyze their throughput numerically and show that the throughput has a trade-off that accords with the length of the CD period. Consequently, we obtain the optimal length of the CD period that maximizes the throughput as a closed-form solution. Analysis and simulation results show that the throughput of distributed collision detection protocols is considerably improved when the optimal CD period is allocated according to the number of stations and the length of the transmitted packet.

• Journal of Power Electronics
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• v.10 no.6
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• pp.762-768
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• 2010

This paper describes the development of a new islanding detection method for inverter-based distributed generation systems, which uses a signal cross-correlation scheme between the injected reactive current and the power frequency deviation. The proposed method injects 1% of the reactive current to the rated current which brings about a negligible degradation of the power quality. It discriminates the islanding state, when the calculated cross-correlation index is larger than 0.5. The operational feasibility was verified through computer simulations with PSCAD/EMTDC software and experimental research with a hardware prototype. The proposed method can detect the islanding state without degrading the power quality at the point of common connection. Further study is required to overcome the cancellation of the injected reactive current from multiple distributed generation units interconnected with the utility grid.

• Proceedings of the KIEE Conference
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• summer
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• pp.301-303
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• 2004

This paper presents an islanding detection algorithm based on the second harmonic. When the DG(distributed Generator) was connected with utility supply, for maintenance and repair of equipment, an islanding occurred. So islanding detection algorithm must be developed for safety of human. Although the DG generating power is similar to power consumption. the proposed algorithm can detect the islanding condition very successfully.