• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권2호
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• pp.659-679
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• 2015

Distributed applications are composed of multiple nodes, which exchange information with individual nodes through message passing. Compared with traditional applications, distributed applications have more complex behavior patterns because a large number of interactions and concurrent behaviors exist among their distributed nodes. Thus, it is difficult to detect anomalous behaviors and determine the location and scope of abnormal nodes, and some attacks and misuse cannot be detected. To address this problem, we introduce a method for detecting anomalous behaviors based on process algebra. We specify the architecture of the behavior detection model and the detection algorithm. The anomalous behavior detection and analysis demonstrate that our method is a good discriminator between normal and anomalous behavior characteristics of distributed applications. Performance evaluation shows that the proposed method enhances efficiency without security degradation.

• Korean Journal of Mathematics
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• 제23권1호
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• pp.171-180
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• 2015

It is discovered in [7] that a dielectric material is coated by a plasmonic material of negative permittivity with dissipation, then cloaking by anomalous localized resonance may occur as the dissipation tends to zero. In this paper, we investigate numerically the pointwise behavior of the potential in the shell when cloaking by anomalous localized resonance (CALR) occurs. By changing locations a dipole source, we can observe some localizing properties of the potential in the shell.

• 한국지구과학회지
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• 제23권1호
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• pp.112-118
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• 2002

The anomalous behaviour of animals prior to a large earthquake has been frequently reported from many places throughout the world since ancient times. This study is to experimentally testify what relations exist between the anomalous animal behavior and electric field effect, which is reported due to the piezo-electric effects in a basement rock before earthquake occurrences. We investigated the electric field effects on behaviors of two kinds of rats and birds. Rats show more sensitive anomalous behavior than birds. Even though the current applied to the experimental birds and rats is just a few ${\mu}$A, they show various abnormal behaviors. The anomalous animal behaviors under the small ground electric field may have some relations to the actual phenomena before great earthquake.

• Animal cells and systems
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• 제8권2호
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• pp.89-95
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• 2004

The bush warblers (Cettia diphone) have been recognized to possess two types of songs: a normal song that plays roles in attracting mate and territorial defense, and an anomalous song. The present study suggests that the anomalous song functions as an alarm signal as well as other unknown signals. Field observations and playback experiments on the anomalous song of bush warbler were conducted in order to investigate the contextual information that occurred between sender and receiver. In the field observation, the males frequently emitted anomalous songs to potential predators. The males responded with an anomalous song to stuffed potential predators. The distance from where the anomalous song occurs to the stimulating source varied depending upon the kinds of stimulus. The males of bush warbler possibly show different responses to the anomalous song depending on the level of danger. When the anomalous song was played back to terrestrial males and females, no distinctive behavior was observed. The anomalous song may be sung to defend the territory against predators or to distract invaders from the nest and female because the male and female behaviors were related with the anomalous song and its phonetic characteristics.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.57-64
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• 2001

There are some previous reports that some animals such as rats and birds move in a large group and act abnormally to avoid the large earthquake. This study is to experimentally testify what relations exist between the anomalous animal behavior and electric field effect, which is reported due to the piezoelectric effects in a basement rock before earthquake occurrences. When electric field is applied to the whole bottom of the cage, they show nervous behaviors such as grooming, washing their faces, standing on legs or running around in panic to avoid the electric field. When more strong electric field is applied, they jump with shrieking and mount on the electric line. The rat shows more sensitive anomalous behavior than the bird. Even though the current to the experimental birds and rats is just a few $\mu$A, they react in various ways. The anomalous animal behaviors under the small ground electric field may have some relations to the actual phenomena before great earthquake. This kind of study is quite worthy for the understanding of earthquake precursors.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1390-1393
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• 2005

The hardening model based on the dislocation mechanics is employed to study the experimentally observed high tensile elongations of NiAl along the [110] orientation at intermediate temperatures. In the hardening model proposed, a mobility of dislocation is assumed to be restricted to glide through the slip plane by forest dislocation and thermally activated cross-slip event. Overall deformation behavior of NiAl was greatly influenced by temperature-dependent dislocation mobility that both experimental and simulated yield stresses decreased as temperature increased. The results of simulation showed anomalous hardening behaviors analogous to those of experiment at certain circumstances. This behavior occurred due to the hardening contributions generated by cross-slip events that disable the dislocation motion in the primary slip systems. By comparing simulation results with experiments, it is confirmed that the proposed hardening model can represent anomalous tensile elongations due to the hardening by forest dislocations and cross-slip events.

• International Journal of Computer Science & Network Security
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• 제21권4호
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• pp.131-139
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• 2021

In current time, anomaly detection is the primary concern of the administrative authorities. Suspicious activity identification is shifting from a human operator to a machine-assisted monitoring in order to assist the human operator and react to an unexpected incident quickly. These automatic surveillance systems face many challenges due to the intrinsic complex characteristics of video sequences and foreground human motion patterns. In this paper, we propose a novel approach to detect anomalous human activity using a hybrid approach of statistical model and Genetic Programming. The feature-set of local motion patterns is generated by a statistical model from the video data in an unsupervised way. This features set is inserted to an enhanced Genetic Programming based classifier to classify normal and abnormal patterns. The experiments are performed using publicly available benchmark datasets under different real-life scenarios. Results show that the proposed methodology is capable to detect and locate the anomalous activity in the real time. The accuracy of the proposed scheme exceeds those of the existing state of the art in term of anomalous activity detection.

• 한국위성정보통신학회논문지
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• 제12권3호
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• pp.35-40
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• 2017

위성의 상태를 파악하기 위해 기존에는 OOL(Out-Of-Limit) 방식을 많이 사용하여 왔다. OOL은 특정 텔레메트리의 상위, 하위 문턱 값을 지정하여 해당 값을 벗어날 경우 문제가 발생한 것으로 인식 하는 방식이다. 이 방법은 파라미터의 특성을 파악하여 각각의 문턱 값을 정확히 설정해야 하는 전문 지식과 노력이 필요하고 텔레메트리 값이 문턱값 내에서 비정상적으로 변할 경우는 검출할 수 없다는 문제점이 있다. 이러한 문제를 극복하기 위해 본 논문에서는 위성이 정상 상태일 때 텔레메트리의 통계적 특징 중 러프집합을 이용하여 중요한 것을 선택, 적용하여 퍼지 모델을 구축하고 이상 상태를 구분하는 시스템을 제안한다. 정상 상태의 데이터만 이용하여 모델을 구축하기 때문에 출력값을 비교 하여 사전에 정의되지 않은 비정상 상태의 구분이 가능 하며 다양한 통계 값을 이용하기 때문에 전문 지식 필요 없이 문턱값 내에서 비정상적으로 변하는 텔레메트리를 검출할 수 있다. 제안한 시스템의 동작 확인을 위해 실제 저궤도 관측위성의 배터리 온도 텔레메트리를 적용하여 시험을 수행 하였고 비정규적 운영 상태에 대한 검출이 성공적으로 이루어 졌다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.408-410
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• 1997

An anomalous magnetoresistance effect has been observed at very low temperatures for composite normal metal conductors. This anomalous behavior is due to transverse Hall currents in the composite which would result in increased $I^2R$ losses and a higher effective resistance for the composite conductor. In this paper, transverse current flow and effective resistance of Cu-Al double-strip was analyzed using finite element method for predicting the Hall losses to be resulted in anomalous magnetoresistance effect, and then be able to visualized.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.196-199
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• 1999

The coexistence of the superconductivity and magnetism in the Ho1-xDyxNi2B2C is studied by using Ginzburg-Landau theory. This material violates the standard do Gennes scaling showing the coexistence and complex interplay of superconducting and magnetic order yielding an anomalous phase diagram. We propose a phenomenological model which includes two magnetic and two superconducting order parameters accounting for the multi-band structure of this material. We describe the magnetic fluctuations and order and demonstrate that they lead to anomalous behavior of the upper critical field. The doping dependence of Tc in Ho1-xDyxNi2B2C showing a reentrance behavior are analyzed yielding a very good agreement with experimental data.