• Journal of Advanced Navigation Technology
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• v.19 no.3
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• pp.244-249
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• 2015

High-altitude electromagnetic pulse (HEMP) is generated from a nuclear burst at high altitudes above the Earth, the electromagnetic fields reach the ground nearly simultaneously with regard to the operation time of systems. The aim of this analysis is to inquire about HEMP characteristics and to analyze about effect in orthogonal frequency division multiplexing (OFDM) system. Specifically, HEMP characteristics are classified field sources, spatial coverage, time domain behavior, frequency spectrum and field intensities in this study. Bits error rate (BER) of the receiver with the software simulation is confirmed for the HEMP effect. Q-factor made a difference about interference duration by transfer characteristics of system. When Q factor is smaller, the recovery time from HEMP interference is short. To the contrary, if the Q factor is larger, the recovery duration is lasted longer by 300-600%.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.568-573
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• 2016

Since the existing analog village broadcasting system has some technical problems in applying and degradations in performance due to its old equipments, it had been required to be changed to a digital system and to develop the standardization from now. Therefore, we have analyzed the service coverage in various environments in order to construct an effective digital wireless village broadcasting system. Also, a precise prediction of field strength should be set up in various propagation environments to design a digital radio stations with reliable transmit power. Using these results the received power and the propagation characteristics in various environments can be predicted to establish a standard and the testing service will be deployed in the near future.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.125-130
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• 2015

Techniques, using physical wedge filter and using dynamic wedge filter and FIF(Field in Field) and ISCT(Irregular Surface Compensating Technique), have been developed according to progress of radiation therapy of breast cancer. Measurement of dose was done to judge the usefulness of technique using three cases, non tissue loss after breast conserving operating and tissue loss after breast conserving operating and mastectomy. Dose indexes of breast tissue, CI (Conformity Index), HI (Homogeneity Index) and QOC (Quality of Coverage), dose index of skin, or dose indexes of lung, volume of 50 percent dose and 20 percent dose were estimated and compared. Using dynamic wedge filter is useful plan at non tissue loss allowing for high dose of lung. FIF and ISCT are useful plan at tissue loss. ISCT is useful plan at mastectomy. Henceforth, we need to apply to valid plan and body type and thorax size.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.2139-2151
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• 2014

Embedded system testing, especially long-term reliability testing, of flash memory solutions such as embedded multi-media card, secure digital card and solid-state drive involves strategic decision making related to test sample size to achieve high test coverage. The test sample size is the number of flash memory devices used in a test. Earlier, there were physical limitations on the testing period and the number of test devices that could be used. Hence, decisions regarding the sample size depended on the experience of human testers owing to the absence of well-defined standards. Moreover, a lack of understanding of the importance of the sample size resulted in field defects due to unexpected user scenarios. In worst cases, users finally detected these defects after several years. In this paper, we propose that a large number of potential field defects can be detected if an adequately large test sample size is used to target weak features during long-term reliability testing of flash memory solutions. In general, a larger test sample size yields better results. However, owing to the limited availability of physical resources, there is a limit on the test sample size that can be used. In this paper, we address this problem by proposing a self-adaptive reliability testing scheme to decide the sample size for effective long-term reliability testing.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.41.2-41.2
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• 2014

Hierarchical merging scenario indicates that galaxies go through major and minor merger events during their formation and evolution. As a result of the merging, substructural features of remnants such as stellar stream are shown around a current galaxy system. To find evidence of stellar substructures on M31 system, we used the near-infrared images of JHK filters obtained from the Wide Field Camera (WFCAM) at UKIRT 3.8m. A total sky coverage is an area of about$ 4.5^{\circ}{\times}6^{\circ}$ around M31. Indeed, M31 system which consists of several satellite systems contains stellar substructures such as giant stellar stream, loops, and spurs. By analysing stellar populations on the near-infrared color-magnitude diagrams, we selected member star candidates of each stellar substructure, from which we map out spatial distribution of stars in the vicinity of M31 system. Here, we present spatial density distribution maps of stars on each substructure over the entire field of M31 system. Also, we discuss the possible origin of the substructures and the implications on the galaxy assembly process.

• Progress in Medical Physics
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• v.13 no.1
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• pp.15-20
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• 2002

Optimum field size for the whole body stereotactic radiosurgery was studied. Dose distributions from the various sizes of targets (diameter 1cm to 7cm, icm interval) were used for this study. Planing scores, expressed as the Target Coverage Index (TCI), were calculated for various target Margin ranged 0cm to 0.5cm. Highest scores were obtained for no Margin to the target size. The target Margin -0.5cm to 0cm to the target showed best TCI the cases of the target size larger than 6cm diameter. No Margin or 0.5cm Margin generated best TCI for less than 2cm cases. Prescription to 80~90% gives best results.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1650-1655
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• 2006

Bacteria belonging to the genus Paenibacillus are facultatively anaerobic endospore formers and are attracting growing ecological and agricultural interest, yet their genome information is very limited. The present study surveyed the genomic features of P. polymyxa ATCC $842^T$ using pulse-field gel electrophoresis of restriction fragments and sample genome sequencing of 1,747 reads (approximately 17.5% coverage of the genome). Putative functions were assigned to more than 60% of the sequences. Functional classification of the sequences showed a similar pattern to that of B. subtilis. Sequence analysis suggests nitrogen fixation and antibiotic production by P. polymyxa ATCC $842^T$, which may explain its plant growth-promoting effects.

• Korean Journal of Remote Sensing
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• v.10 no.2
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• pp.121-132
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• 1994

A GIS based tactical terrain analysis system named ATTAS(Army Tactical Terrain Analysis Software) has been designed and implemented to support the field commanders for enhancing the capabiliy of their unit and efficiency of weapon system. This system is designed to provide computer graphics environment in which the analyst can interactively operate the entire analyzing process such as selecting the area of interest, performing analysis functions, simulating required battlefield operation and display the results. This system can be divided into three major sections; the terrain analysis modules, utilites, and graphic editor. The terrain analysis module inclused surface analysis, line of sight analysis, enemy disposition, 3D display, radar coverage, logistic route analysis, shortest path analysis, atmospheric phenomena prediction, automated IPB (Inteligence preparation of Battlefield), and other applied analysis. A combination of 2D and 3D computer graphics techniques using the X-window system with OSF/Motif in UNIX workstation was adopted as the user interface. The integration technique of remotely sensed images and GIS data such as precision registration, overlay, and on-line editing was developed and implemented. An efficient image and GIS data management technique was also developed and implemented using Oracle Database Management System.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.11
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• pp.4310-4330
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• 2020

With the continuous emergence of new applications and cyberattacks and their frequent updates, the need for automatic protocol reverse engineering is gaining recognition. Although several methods for automatic protocol reverse engineering have been proposed, each method still faces major limitations in extracting clear specifications and in its universal application. In order to overcome such limitations, we propose an automatic protocol reverse engineering method using a two-pathway model based on a contiguous sequential pattern (CSP) algorithm. By using this model, the method can infer both command-oriented protocols and non-command-oriented protocols clearly and in detail. The proposed method infers all the key elements of the protocol, which are syntax, semantics, and finite state machine (FSM), and extracts clear syntax by defining fine-grained field types and three types of format: field format, message format, and flow format. We evaluated the efficacy of the proposed method over two non-command-oriented protocols and three command-oriented protocols: the former are HTTP and DNS, and the latter are FTP, SMTP, and POP3. The experimental results show that this method can reverse engineer with high coverage and correctness rates, more than 98.5% and 99.1% respectively, and be general for both command-oriented and non-command-oriented protocols.

• Journal of Public Diplomacy
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• v.1 no.1
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• pp.80-110
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• 2021

Public diplomacy (PD) scholars tend to consider two main principals: the country or agent that conducts PD (Actor A), and target groups in the host country in which PD is conducted (Actor B). The field currently lacks theories of how communications between Actors A and B can be disrupted by a third party, such as a group of motivated trolls, an organised advocacy group, or a hostile country and its agents. The purpose of this article is to outline some theoretical considerations for how the PD research field might move away from a two-actor model of PD to one in which disruption is part of the discussion. The case study explores the activities of an interest group called Media Watchdogs of Sweden (MEWAS). MEWAS was a group of around 200 members who met in a hidden Facebook group to coordinate off-platform activities aimed at influencing perceptions of how the Swedish government handled the COVID-19 pandemic in the eyes of foreign governments, researchers, decision-makers, and media. Much critical news coverage in the international press has been linked to this group. Unpacking some of MEWAS' activities, which can be considered a quite typical mixture of legitimate and illegitimate communication techniques used by activist groups, can help to shed light on some difficult questions regarding disruption in PD.