• Journal of Astronomy and Space Sciences
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• v.39 no.4
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• pp.145-158
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• 2022

The dynamics of the outer zone radiation belt has received a lot of attention mainly due to the correlation between the occurrence of enhancing relativistic electron flux and spacecraft operation anomalies or even failures (e.g., Baker et al. 1994). Relativistic electron events are often observed during great storms associated with ultra low frequency (ULF) waves. For example, a large buildup of relativistic electrons was observed during the great storm of March 24, 1991 (e.g., Li et al. 1993; Hudson et al. 1995; Mann et al. 2013). However, the dominant processes which accelerate magnetospheric radiation belt electrons to MeV energies are not well understood. In this paper, we present observations of Pc5 ULF waves in the recovery phase of the Bastille day storm of July 16, 2000 and electron and proton flux simultaneously oscillating with the same frequencies as the waves. The mechanism for the observed electron and proton flux modulations is examined using ground-based and satellite observations. During this storm time, multiple packets of discrete frequency Pc5 ULF waves appeared associated with energetic particle flux oscillations. We model the drift paths of electrons and protons to determine if the particles drift through the ULF wave to understand why some particle fluxes are modulated by the ULF waves and others are not. We also analyze the flux oscillations of electrons and protons as a function of energy to determine if the particle modulations are caused by a ULF wave drift resonance or advection of a particle density gradient. We suggest that the energetic electron and proton modulations by Pc5 ULF waves provide further evidence in support of the important role that ULF waves play in outer radiation belt dyanamics during storm times.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.4
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• pp.51-61
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• 2009

Recently, the cyber-attacks using botnets are being increased, Because these attacks pursue the money, the criminal aspect is also being increased, There are spreading of spam mail, DDoS(Distributed Denial of Service) attacks, propagations of malicious codes and malwares, phishings. leaks of sensitive informations as cyber-attacks that used botnets. There are many studies about detection and mitigation techniques against centralized botnets, namely IRC and HITP botnets. However, P2P botnets are still in an early stage of their studies. In this paper, we analyzed the traffics of the Peacomm bot that is one of P2P-based storm bot by using honeynet which is utilized in active analysis of network attacks. As a result, we could see that the Peacomm bot sends a large number of UDP packets to the zombies in wide network through P2P. Furthermore, we could know that the Peacomm bot makes the scale of botnet maintained and extended through these results. We expect that these results are used as a basis of detection and mitigation techniques against P2P botnets.

• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.105-113
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• 2014

Equine herpesvirus type 1 (EHV-1) is an economically important pathogen of horses and exerts its major impact by inducing abortion storms and sporadic abortions in pregnant mares, early neonatal death in foals, and respiratory disease in young horses. Although equine herpesvirus type 4 (EHV-4) rarely causes clinical manifestations of disease in organs other than the respiratory track, isolated cases of myeloencephalopathy and sporadic abortions have been reported in EHV-4 infections. Here, we report an abortion storm in Thoroughbred breeding farms in Jeju island, South Korea. It occurred for 16 days from first abortion to last one. There were no clinical signs prior to abortion and stillbirth in broodmares. Two PCR-primers were made on glycoprotein B gene of EHV-1 and EHV-4 to amplify specific common regions of the viruses. We could detect the virus specific genes in aborted samples by PCR, and concluded that the cause of abortion storm was EHV infection. This report describes the first abortion storm case caused by EHV in Thoroughbred breeding farms in South Korea.

• Korean Journal of Veterinary Service
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• v.46 no.2
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• pp.167-173
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• 2023

An 8-year-old female neutered Maltese dog exhibited signs of serious thunderstorm phobia including panting, wandering, shivering, hiding, crying or whining, or trying to escape from the house. In this study, we administered clomipramine and alprazolam and observed behavioral improvement for 3 years. Clinical symptoms measured according to the storm phobia assessment (SPA) were significantly high with an initial total score of 19 points. However, it improved to a total score of 8 on day 176 after drugs administration and returned to the normal level with the total score of 5 points on the 983 days. When the symptoms for the first 4 treatments and the last 4 treatments were compared in 2 groups, the total score of all clinical symptoms decreased to -62.83% in the last 4 treatments. This study found that treatment with alprazolam and clomipramine was associated with a decrease in clinical signs of storm anxiety, suggesting that two drugs would be effective in reducing symptoms caused by anxiety, thunderstorm phobia, and noise phobia. In this follow up study, we hope that more studies would be conducted on behavior modification for treatment of storm phobia in veterinary medicine.

• Journal of the Korea Society of Computer and Information
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• v.29 no.7
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• pp.1-9
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• 2024

In this paper, we propose BRAIDS, a boot storm mitigation plan consisting of an AI-based VDI usage prediction system and a virtual machine boot scheduler system, to alleviate boot storms and improve service stability. Virtual Desktop Infrastructure (VDI) is an important technology for improving an organization's work productivity and increasing IT infrastructure efficiency. Boot storms that occur when multiple virtual desktops boot simultaneously cause poor performance and increased latency. Using the xgboost algorithm, existing VDI usage data is used to predict future VDI usage. In addition, it receives the predicted usage as input, defines a boot storm considering the hardware specifications of the VDI server and virtual machine, and provides a schedule to sequentially boot virtual machines to alleviate boot storms. Through the case study, the VDI usage prediction model showed high prediction accuracy and performance improvement, and it was confirmed that the boot storm phenomenon in the virtual desktop environment can be alleviated and IT infrastructure can be utilized efficiently through the virtual machine boot scheduler.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.435-440
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• 2004

Most of our GIS implementation activities have been focussed on the management of urban information in local municipalities. Management of urban facilities has been the major issue of concern and has little role in providing the decision maker with alternatives from which one can analyse and choose the optimum solution. For this reason, the spatial decision support system is in need. Business analysis software is effectively used for site analysis of new stores, customer prospecting and other issues of decision making for business purposes, The same geoprocessing module of business analysis software would be useful if put to use for the management of disaster management especially for storm surge management. Application of the business analysis model for disaster management has been reviewed. Specially in case of storm surge, where quick response is crucial, the spatial decision support system will be most effective.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.111-114
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• 2007

One of future remote sensing techniques for the estimation of damage by storm and flood is the extraction of water area, which could be the basis of measuring the damage by storm and flood and estimate restoration cost. This paper introduces an approach to damage estimation using satellite Image. The project site was Ansung area and a set of Radarsat-1 SAR image at 6.25m resolution was used for the test. Authors investigated methods of SAR image processing such as shadow-effect removal, orthorectification of SAR image and calculation of damage area by flood. Consequetly, this study showed that technique improvement of image processing and the best of result for extracting water area. Also, found the new possibility of damage estimation using satellite image.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.526-529
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• 2007

Storm and flood damage management systems in national disaster management system(NDMS) were organized into three operation systems. They are prevention, preparation, response, and recovery systems. Disaster resources in each system must be promptly and exactly applied to minimize casualties and loss of properties. However, the disaster resources in current management system can not be immediately used in calamity situation due to the lack of efficiency in statistical data. In this study, the classification system of the disaster resources in storm and flood damage systems was examined to develop the a standard technology in disaster resources management. Problems and reformation points of the classification system were also presented to improve the classification technique and to construct the data base.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1093-1102
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• 2009

This study was focused on analyse Nonpoint source characteristics from Flat slope field and Steep slope field. We performed Storm-water monitering for obtain flow data and concentration data. Totally, eleven times Event was occurred. We calculated EMC(Event Mean Concentration) and Pollutants Loads using data we obtained. As a result, steep slope field has more discharge than flat field. SS value, one of the water quality contents, has largest variation and T-N has least variation. There is runoff differences even though events has same rainfall. We assume that not only amount of Rainfall, but also Rainfall Duration Times, Intensity, Number of Previous Non-precipitation days can affect to Run-off.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04a
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• pp.691-693
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• 2004

Mobile Ad hoc network은 stationary infrastructure의 도움 없이 이동 노드들이 필요 시 multi-hop wireless links network 형태를 구성하여 통신이 이루어지게 하는 network이다. 따라서 효율적인 라우팅 프로토콜의 개발이 중요한 issue인데 최근에는 routing overhead가 적은 on-demand 프로토콜이 주목을 받고 있다. On-demand 프로토콜은 새로운 route을 구성하기 위해서 query packet을 broadcasting하게 되는데, 특히 노드들의 mobility가 많은 mobile ad hoc network(MANET)의 경우에는 더욱더 자주 발생하게 되는데, blind broadcasting은 neighbor 노드들 간의 radio transmission region overlap에 의해 redundancy, contention, collision 같은 broadcast storm 문제를 발생시키게 된다. 본 논문은 on-demand 프로토콜의 broadcast storm 문제를 해결하기 위해 Neighbor Topology을 고려 한 Dynamic Adaptation Query flooding scheme을 제시한다. 또한 Dynamic Adaptive Query flooding scheme은 broadcast storm 문제 해결뿐만 아니라 network의 congestion을 감소시켜 data packet의 성능 향상에도 기여 할 것이다.